don't remove `vendor/bundle` twice
don't remove `vendor/bundle` twice

fcruxen/ruby-buildpack,mattmanning/heroku-buildpack-ruby-jekyll,ascot21/heroku-buildpack-turbo-sprockets,davidjrice/heroku-buildpack-couchbase-ruby,orenyk/heroku-buildpack-ruby,sgnpa/heroku-buildpack-cas,codykrieger/heroku-buildpack-jekyll,stolt45/heroku-buildpack-ruby-with-sqlite3,fcruxen/ruby-buildpack,daltonrenaldo/heroku-buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk-new,Jonty/ruby-buildpack,simonnordberg/heroku-buildpack-ruby,beydogan/ruby-buildpack,tdenovan/heroku-buildpack-ruby,icelab/heroku-buildpack-ruby,jonasoberschweiber/heroku-buildpack-ruby,codykrieger/heroku-buildpack-jekyll,jasonlevens/heroku-buildpack-ruby,joshco/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,makifund/heroku-buildpack-ruby,jonasoberschweiber/heroku-buildpack-ruby,ibmdb/db2rubybuildpack,musicglue/heroku-buildpack-ruby,electricobjects/heroku-buildpack-ruby,dtao/teeny-buildpack,rowanoulton/heroku-buildpack-ruby,tenjikinc/heroku-buildpack-ruby,jumptvs/BP_Ruby,Altoros/ruby-buildpack,KoanHealth/heroku-buildpack-marvin-setup,rowanoulton/heroku-buildpack-ruby,ablease/custom-buildpack,swipesense/heroku-buildpack-ruby,meskyanichi/heroku-buildpack-middleman,millie/heroku-buildpack-ruby-with-pdftk,heroku/heroku-buildpack-ruby,makifund/heroku-buildpack-ruby,leonardykris/mos-ruby-buildpack,bskyb-commerce/ruby-buildpack,takii/db2rubybuildpack,ibmdb/db2rubybuildpack,ruby/heroku-buildpack-www-ruby-lang,Altoros/ruby-buildpack,packetmonkey/heroku-buildpack-ruby,zoomer/heroku-buildpack-ruby-bower,bskyb-commerce/help-heroku-buildpack,awebneck/heroku-buildpack-canvas,vhx/heroku-buildpack,davidjrice/heroku-buildpack-couchbase-ruby,ndbroadbent/heroku-buildpack-turbo-sprockets,adaptivelab/heroku-buildpack-adaptivelab-website-2,hellojustin/heroku-buildpack-custom-ruby,mintybit/heroku-buildpack-ruby,pavgup/heroku-buildpack-ruby-lateslugignore,instacart/heroku-buildpack-ruby,jcamenisch/heroku-buildpack-rgeo,ilpoldo/heroku-buildpack-ruby,Genius/heroku-buildpack-ruby,fgbreel/heroku-buildpack-ruby,firmhouse/heroku-buildpack-ruby-freetds,jglascoe/heroku-buildpack-ruby-jekyll,gbenedict/heroku-buildpack-ruby,simonnordberg/heroku-buildpack-ruby,dtao/deft-buildpack-ruby,mperejda/heroku-buildpack-ruby,cloudn/buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk-new,wakermahmud/heroku-buildpack-jekyll,DigitalInnovation/heroku-buildpack-mslabs,pkgr/buildpack-ruby-precise-old,tomwolfe/heroku-buildpack-gsl-ruby,takii/db2rubybuildpack,ejholmes/heroku-buildpack-middleman,derrek/heroku-buildpack-ruby,mattmanning/heroku-buildpack-ruby-jekyll,mrhenry/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,d-reinhold/cf-buildpack-ruby,takii/db2rubybuildpack,mattwalters/heroku-buildpack-ruby,allomov/fat-free-heroku-buildpack-ruby,ChefSteps/heroku-buildpack-ruby,ablease/custom-buildpack,phusion/heroku-buildpack-ruby,guidance-guarantee-programme/heroku-buildpack-princexml-old,crdschurch/heroku-buildpack-ruby,wakermahmud/heroku-buildpack-jekyll,ericroberts/heroku-buildpack-ruby,tenjikinc/heroku-buildpack-ruby,Dim25/heroku-buildpack-ruby-GSL,iamjarvo/ruby-buildpack,mattwalters/heroku-buildpack-ruby,amaltson/heroku-buildpack-ruby,qstream/heroku-buildpack-ruby,hatofmonkeys/ruby-testing-buildpack,d-reinhold/cf-buildpack-ruby,jgarber/heroku-buildpack-ruby-octopress,jeremyvdw/heroku-buildpack-ruby-jekyll,cloudfoundry/ruby-buildpack,thewebguy/heroku-buildpack-ruby-ffmpeg-libsndfile,moneyadviceservice/heroku-buildpack-ruby-bowndler,bellycard/heroku-buildpack-ruby,ilpoldo/heroku-buildpack-ruby,shuber/heroku-buildpack-ruby,swipesense/heroku-buildpack-ruby,instacart/heroku-buildpack-ruby,trumaker/heroku-buildpack-turbo-sprockets,0x00evil/heroku-buildpack-ruby,Dim25/heroku-buildpack-ruby-GSL,hpcloud/ruby-buildpack,redhotvengeance/heroku-buildpack-deep-thought,hausdorff/heroku-buildpack-ruby-jekyll,gbenedict/heroku-buildpack-ruby,jgarber/heroku-buildpack-ruby-octopress,Scalingo/ruby-buildpack,moneyadviceservice/heroku-buildpack-ruby-bowndler,lemurheavy/heroku-buildpack-ruby,crdschurch/heroku-buildpack-ruby,diasks2/heroku-buildpack-mecab,hatofmonkeys/ruby-testing-buildpack,jumptvs/BP_Ruby,packetmonkey/heroku-buildpack-ruby,stolt45/heroku-buildpack-ruby-with-sqlite3,Numerico/heroku-buildpack-ruby,zidekmat/buildpack-ruby,DyegoCosta/heroku-buildpack-ruby,CPPWind/ruby-buildpack,gls1/heroku-buildpack-ruby-pdftk,dtao/deft-buildpack-ruby,guidance-guarantee-programme/heroku-buildpack-princexml-old,pilotcreative/heroku-buildpack-ruby,bskyb-commerce/help-heroku-buildpack,ekaranto/rails4-bluemix-buildpack,dlorson/gentle-buildpack,rhomobile/heroku-buildpack-ruby,ibmdb/db2rubybuildpack,zunda/heroku-buildpack-ruby,jeremyvdw/heroku-buildpack-ruby-jekyll,travis-ci/heroku-buildpack-ruby,ericboehs/heroku-buildpack-ruby,Genius/heroku-buildpack-ruby,qnyp/heroku-buildpack-ruby-bower,cloudn/buildpack-ruby,stefansundin/heroku-buildpack-ruby,stefansundin/heroku-buildpack-ruby,takii/heroku-buildpack-ruby,Jonty/ruby-buildpack,michaelphines/alexa-nest,HYPERHYPER/heroku-buildpack-ruby,fgbreel/heroku-buildpack-ruby,icelab/heroku-buildpack-ruby,sanemat/heroku-buildpack-ruby-tachikoma,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,rstacruz/heroku-buildpack-middleman,scottatron/moc-buildpack,heroku/heroku-buildpack-ruby,ChefSteps/heroku-buildpack-ruby,schu/buildpack-testing,lemurheavy/heroku-buildpack-ruby,firmhouse/heroku-buildpack-ruby-freetds,leonardykris/mos-ruby-buildpack,jgable/buildpack-ruby-rack-setup-tasks,DouglasAllen/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,donnykurnia/heroku-buildpack-ruby,redhotvengeance/heroku-buildpack-deep-thought,derrek/heroku-buildpack-ruby,phusion/heroku-buildpack-ruby,bwaite-jaroop/heroku-buildpack-ruby,ActiveState/heroku-buildpack-ruby,lyoshenka/heroku-buildpack-ruby-jekyll,WilliamDenniss/heroku-buildpack-ruby-imagemagick,ekaranto/rails4-bluemix-buildpack,shuber/heroku-buildpack-ruby,Jonty/ruby-buildpack,Altoros/ruby-buildpack,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,mperejda/heroku-buildpack-ruby,righi/instacart-heroku-buildpack,pkgr/heroku-buildpack-ruby,jasonlevens/heroku-buildpack-ruby,meskyanichi/heroku-buildpack-middleman,DyegoCosta/heroku-buildpack-ruby,tdenovan/heroku-buildpack-ruby,engineyard/heroku-buildpack-ruby,AdStage/heroku-buildpack-ruby,jayshreeanand/heroku-buildpack-ruby,dieze/heroku-buildpack-ruby-hooks,jonseaberg/heroku-buildpack-turbo-sprockets,bskyb-commerce/ruby-buildpack,sgnpa/heroku-buildpack-cas,jgarber/heroku-buildpack-ruby-octopress,cordata/heroku-buildpack-ruby,sky-uk/ruby-buildpack,WilliamDenniss/heroku-buildpack-ruby-imagemagick,electricobjects/heroku-buildpack-ruby,jonseaberg/heroku-buildpack-turbo-sprockets,thirdprestige/heroku-buildpack-ruby,joshco/heroku-buildpack-ruby,takii/db2rubybuildpack,ablease/custom-buildpack,nicholasmott/heroku-buildpack-octopress,wolfoo2931/heroku-buildpack-ruby-2a352ae,bellycard/heroku-buildpack-ruby,tpope/heroku-buildpack-ruby-tpope,cloudfoundry/ruby-buildpack,darron/heroku-buildpack-ruby-jekyll,vhx/heroku-buildpack,Altoros/ruby-buildpack,hpcloud/heroku-buildpack-ruby,sstelfox/buildpack-ruby,teodor-pripoae/heroku-buildpack-ruby,beydogan/ruby-buildpack,diasks2/heroku-buildpack-mecab,erintherad/heroku-buildpack-ruby,progrium/heroku-buildpack-ruby,DigitalInnovation/heroku-buildpack-mslabs,daltonrenaldo/heroku-buildpack-ruby,teodor-pripoae/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,erintherad/heroku-buildpack-ruby,hpcloud/ruby-buildpack,sky-uk/ruby-buildpack,CPPWind/ruby-buildpack,anay/buildpack-ruby-with-oracle-jdk,dleavitt/heroku-buildpack-ruby,pkgr/buildpack-ruby-precise-old,bskyb-commerce/ruby-buildpack,pkgr/buildpack-ruby-precise-old,brightbytes/heroku-buildpack-ruby-without-assets-precompile,zunda/heroku-buildpack-ruby,rvizza/heroku-buildpack-gsl-ruby,0x00evil/heroku-buildpack-ruby,qnyp/heroku-buildpack-ruby-bower,12spokes/heroku-buildpack-ruby-imagemagick,sanemat/heroku-buildpack-ruby-tachikoma,gls1/heroku-buildpack-ruby-pdftk,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,schu/buildpack-testing,jumptvs/BP_Ruby,millie/heroku-buildpack-ruby-with-pdftk,rstacruz/heroku-buildpack-middleman,rvizza/heroku-buildpack-gsl-ruby,sstelfox/buildpack-ruby,reesio/heroku-buildpack-ruby,Jonty/ruby-buildpack,blueapron/heroku-buildpack-ruby,allomov/fat-free-heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,sky-uk/ruby-buildpack,pilotcreative/heroku-buildpack-ruby,sky-uk/ruby-buildpack,adaptivelab/heroku-buildpack-adaptivelab-website-2,orenyk/heroku-buildpack-ruby,jumptvs/BP_Ruby,hpcloud/heroku-buildpack-ruby,progrium/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,aarongray/heroku-buildpack-ruby,atmos/heroku-buildpack-ruby,dtao/teeny-buildpack,recursecenter/heroku-buildpack-ruby,aarongray/heroku-buildpack-ruby,atmos/heroku-buildpack-ruby,ejholmes/heroku-buildpack-middleman,pavgup/heroku-buildpack-ruby-lateslugignore,catalyzeio/buildpack-ruby,catalyzeio/buildpack-ruby,hatofmonkeys/ruby-testing-buildpack,awebneck/heroku-buildpack-canvas,orlando/heroku-buildpack-ruby,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,ablease/custom-buildpack,wolfoo2931/heroku-buildpack-ruby-2a352ae,bskyb-commerce/ruby-buildpack,jgable/buildpack-ruby-rack-setup-tasks,barakav/heroku-buildpack-ruby,ericboehs/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,musicglue/heroku-buildpack-ruby,reesio/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,HYPERHYPER/heroku-buildpack-ruby,pkgr/heroku-buildpack-ruby,cmaggard/heroku-buildpack-turbo-sprockets,darron/heroku-buildpack-ruby-jekyll,ActiveState/heroku-buildpack-ruby,jcamenisch/heroku-buildpack-rgeo,schu/heroku-buildpack-ruby,Numerico/heroku-buildpack-ruby,lyoshenka/heroku-buildpack-ruby-jekyll,12spokes/heroku-buildpack-ruby-imagemagick,andycroll/heroku-buildpack-jekyll,progrium/heroku-buildpack-ruby,Scalingo/ruby-buildpack,ltrademark/heroku-buildpack-ruby,mintybit/heroku-buildpack-ruby,trumaker/heroku-buildpack-turbo-sprockets,CPPWind/ruby-buildpack,zidekmat/buildpack-ruby,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,ltrademark/heroku-buildpack-ruby,recursecenter/heroku-buildpack-ruby,pcincalifornia/wdc-heroku-buildpack-middleman,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,dleavitt/heroku-buildpack-ruby,jglascoe/heroku-buildpack-ruby-jekyll,nicholasmott/heroku-buildpack-octopress,hixi/heroku-buildpack-ruby,CPPWind/ruby-buildpack,bwaite-jaroop/heroku-buildpack-ruby,cloudControl/buildpack-ruby,nthj/heroku-buildpack-mirror,Micka33/heroku-buildpack-ruby-liblua,michaelphines/alexa-nest,orlando/heroku-buildpack-ruby,qstream/heroku-buildpack-ruby,rhomobile/heroku-buildpack-ruby,space150/heroku-buildpack-ruby,travis-ci/heroku-buildpack-ruby,thirdprestige/heroku-buildpack-ruby,space150/heroku-buildpack-ruby,ericroberts/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,fcruxen/ruby-buildpack,dieze/heroku-buildpack-ruby-hooks,andycroll/heroku-buildpack-jekyll,atmos/heroku-buildpack-ruby,thirdprestige/heroku-buildpack-ruby,cordata/heroku-buildpack-ruby,pietrop/heroku-buildpack-ruby,zoomer/heroku-buildpack-ruby-bower,tomwolfe/heroku-buildpack-gsl-ruby,phusion/heroku-buildpack-ruby,AdStage/heroku-buildpack-ruby,Micka33/heroku-buildpack-ruby-liblua,hpcloud/ruby-buildpack,KoanHealth/heroku-buildpack-marvin-setup,hellojustin/heroku-buildpack-custom-ruby,hpcloud/ruby-buildpack,pavgup/heroku-buildpack-ruby-lateslugignore,righi/instacart-heroku-buildpack,donnykurnia/heroku-buildpack-ruby,Numerico/heroku-buildpack-ruby,engineyard/heroku-buildpack-ruby,cloudControl/buildpack-ruby,ascot21/heroku-buildpack-turbo-sprockets,thewebguy/heroku-buildpack-ruby-ffmpeg-libsndfile,firmhouse/heroku-buildpack-ruby-freetds,amaltson/heroku-buildpack-ruby,AdStage/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,nicholasmott/heroku-buildpack-octopress,ndbroadbent/heroku-buildpack-turbo-sprockets,barakav/heroku-buildpack-ruby,takii/heroku-buildpack-ruby,hixi/heroku-buildpack-ruby,Git-Host/prelang-buildpack,Git-Host/prelang-buildpack,sanemat/heroku-buildpack-ruby-tachikoma,centresource/heroku-buildpack-turbo-sprockets-pmp-ffm,fcruxen/ruby-buildpack,cloudn/buildpack-ruby,d-reinhold/cf-buildpack-ruby,hausdorff/heroku-buildpack-ruby-jekyll,sgnpa/heroku-buildpack-cas,schu/heroku-buildpack-ruby,jayshreeanand/heroku-buildpack-ruby,lemurheavy/heroku-buildpack-ruby,travis-ci/heroku-buildpack-ruby,pcincalifornia/wdc-heroku-buildpack-middleman,brightbytes/heroku-buildpack-ruby-without-assets-precompile,cloudn/buildpack-ruby,pietrop/heroku-buildpack-ruby,sky-uk/help-heroku-buildpack,sky-uk/help-heroku-buildpack,WilliamDenniss/heroku-buildpack-ruby-imagemagick,mrhenry/heroku-buildpack-ruby,cmaggard/heroku-buildpack-turbo-sprockets,blueapron/heroku-buildpack-ruby,davidjrice/heroku-buildpack-couchbase-ruby,tpope/heroku-buildpack-ruby-tpope,anay/buildpack-ruby-with-oracle-jdk,dlorson/gentle-buildpack,nthj/heroku-buildpack-mirror,DouglasAllen/heroku-buildpack-ruby,scottatron/moc-buildpack