add rake tasks for checking if the changelog exists and staging a buildpack tarball
add rake tasks for checking if the changelog exists and staging a buildpack tarball

moneyadviceservice/heroku-buildpack-ruby-bowndler,catalyzeio/buildpack-ruby,space150/heroku-buildpack-ruby,icelab/heroku-buildpack-ruby,scottatron/moc-buildpack,jonasoberschweiber/heroku-buildpack-ruby,Micka33/heroku-buildpack-ruby-liblua,erintherad/heroku-buildpack-ruby,sky-uk/ruby-buildpack,Altoros/ruby-buildpack,qstream/heroku-buildpack-ruby,Jonty/ruby-buildpack,hatofmonkeys/ruby-testing-buildpack,DyegoCosta/heroku-buildpack-ruby,Dim25/heroku-buildpack-ruby-GSL,Git-Host/prelang-buildpack,dleavitt/heroku-buildpack-ruby,dleavitt/heroku-buildpack-ruby,fcruxen/ruby-buildpack,righi/instacart-heroku-buildpack,ascot21/heroku-buildpack-turbo-sprockets,CPPWind/ruby-buildpack,catalyzeio/buildpack-ruby,takii/db2rubybuildpack,mattmanning/heroku-buildpack-ruby-jekyll,tpope/heroku-buildpack-ruby-tpope,sstelfox/buildpack-ruby,engineyard/heroku-buildpack-ruby,swipesense/heroku-buildpack-ruby,dtao/teeny-buildpack,ericboehs/heroku-buildpack-ruby,cloudn/buildpack-ruby,ericroberts/heroku-buildpack-ruby,zoomer/heroku-buildpack-ruby-bower,takii/db2rubybuildpack,pilotcreative/heroku-buildpack-ruby,jasonlevens/heroku-buildpack-ruby,sky-uk/ruby-buildpack,ablease/custom-buildpack,barakav/heroku-buildpack-ruby,pkgr/heroku-buildpack-ruby,redhotvengeance/heroku-buildpack-deep-thought,ChefSteps/heroku-buildpack-ruby,Micka33/heroku-buildpack-ruby-liblua,iamjarvo/ruby-buildpack,tdenovan/heroku-buildpack-ruby,stolt45/heroku-buildpack-ruby-with-sqlite3,heroku/heroku-buildpack-ruby,awebneck/heroku-buildpack-canvas,ablease/custom-buildpack,hellojustin/heroku-buildpack-custom-ruby,Scalingo/ruby-buildpack,rvizza/heroku-buildpack-gsl-ruby,orlando/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,guidance-guarantee-programme/heroku-buildpack-princexml-old,jumptvs/BP_Ruby,lyoshenka/heroku-buildpack-ruby-jekyll,ilpoldo/heroku-buildpack-ruby,shuber/heroku-buildpack-ruby,schu/heroku-buildpack-ruby,andycroll/heroku-buildpack-jekyll,beydogan/ruby-buildpack,recursecenter/heroku-buildpack-ruby,mperejda/heroku-buildpack-ruby,michaelphines/alexa-nest,trumaker/heroku-buildpack-turbo-sprockets,bskyb-commerce/help-heroku-buildpack,Altoros/ruby-buildpack,Jonty/ruby-buildpack,dtao/deft-buildpack-ruby,reesio/heroku-buildpack-ruby,d-reinhold/cf-buildpack-ruby,zunda/heroku-buildpack-ruby,barakav/heroku-buildpack-ruby,tenjikinc/heroku-buildpack-ruby,electricobjects/heroku-buildpack-ruby,teodor-pripoae/heroku-buildpack-ruby,orlando/heroku-buildpack-ruby,mrhenry/heroku-buildpack-ruby,bwaite-jaroop/heroku-buildpack-ruby,Scalingo/ruby-buildpack,crdschurch/heroku-buildpack-ruby,hellojustin/heroku-buildpack-custom-ruby,hpcloud/ruby-buildpack,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,KoanHealth/heroku-buildpack-marvin-setup,codykrieger/heroku-buildpack-jekyll,Git-Host/prelang-buildpack,0x00evil/heroku-buildpack-ruby,tenjikinc/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,ltrademark/heroku-buildpack-ruby,cloudControl/buildpack-ruby,rowanoulton/heroku-buildpack-ruby,ablease/custom-buildpack,pilotcreative/heroku-buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk-new,DouglasAllen/heroku-buildpack-ruby,takii/heroku-buildpack-ruby,righi/instacart-heroku-buildpack,ibmdb/db2rubybuildpack,recursecenter/heroku-buildpack-ruby,trumaker/heroku-buildpack-turbo-sprockets,iamjarvo/ruby-buildpack,swipesense/heroku-buildpack-ruby,fcruxen/ruby-buildpack,cloudn/buildpack-ruby,zoomer/heroku-buildpack-ruby-bower,cloudfoundry/ruby-buildpack,beydogan/ruby-buildpack,stefansundin/heroku-buildpack-ruby,jonasoberschweiber/heroku-buildpack-ruby,daltonrenaldo/heroku-buildpack-ruby,dtao/deft-buildpack-ruby,sky-uk/ruby-buildpack,jonseaberg/heroku-buildpack-turbo-sprockets,mintybit/heroku-buildpack-ruby,diasks2/heroku-buildpack-mecab,schu/buildpack-testing,takii/db2rubybuildpack,engineyard/heroku-buildpack-ruby,rvizza/heroku-buildpack-gsl-ruby,Jonty/ruby-buildpack,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,mintybit/heroku-buildpack-ruby,dieze/heroku-buildpack-ruby-hooks,bskyb-commerce/ruby-buildpack,zunda/heroku-buildpack-ruby,ericboehs/heroku-buildpack-ruby,cloudControl/buildpack-ruby,simonnordberg/heroku-buildpack-ruby,ibmdb/db2rubybuildpack,hatofmonkeys/ruby-testing-buildpack,codykrieger/heroku-buildpack-jekyll,instacart/heroku-buildpack-ruby,teodor-pripoae/heroku-buildpack-ruby,wakermahmud/heroku-buildpack-jekyll,stolt45/heroku-buildpack-ruby-with-sqlite3,Genius/heroku-buildpack-ruby,allomov/fat-free-heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,tdenovan/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,takii/heroku-buildpack-ruby,makifund/heroku-buildpack-ruby,dtao/teeny-buildpack,vhx/heroku-buildpack,orenyk/heroku-buildpack-ruby,Genius/heroku-buildpack-ruby,anay/buildpack-ruby-with-oracle-jdk,bskyb-commerce/ruby-buildpack,sky-uk/ruby-buildpack,hixi/heroku-buildpack-ruby,jgable/buildpack-ruby-rack-setup-tasks,tomwolfe/heroku-buildpack-gsl-ruby,ilpoldo/heroku-buildpack-ruby,hpcloud/ruby-buildpack,makifund/heroku-buildpack-ruby,jayshreeanand/heroku-buildpack-ruby,Jonty/ruby-buildpack,ltrademark/heroku-buildpack-ruby,allomov/fat-free-heroku-buildpack-ruby,ibmdb/db2rubybuildpack,mattwalters/heroku-buildpack-ruby,bellycard/heroku-buildpack-ruby,musicglue/heroku-buildpack-ruby,d-reinhold/cf-buildpack-ruby,leonardykris/mos-ruby-buildpack,ekaranto/rails4-bluemix-buildpack,heroku/heroku-buildpack-ruby,jonseaberg/heroku-buildpack-turbo-sprockets,simonnordberg/heroku-buildpack-ruby,DigitalInnovation/heroku-buildpack-mslabs,tpope/heroku-buildpack-ruby-tpope,gbenedict/heroku-buildpack-ruby,sky-uk/help-heroku-buildpack,bwaite-jaroop/heroku-buildpack-ruby,cloudfoundry/ruby-buildpack,leonardykris/mos-ruby-buildpack,ekaranto/rails4-bluemix-buildpack,ChefSteps/heroku-buildpack-ruby,diasks2/heroku-buildpack-mecab,zidekmat/buildpack-ruby,cordata/heroku-buildpack-ruby,ekaranto/rails4-bluemix-buildpack,pkgr/heroku-buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk,ericroberts/heroku-buildpack-ruby,awebneck/heroku-buildpack-canvas,Altoros/ruby-buildpack,cloudfoundry/ruby-buildpack,pietrop/heroku-buildpack-ruby,donnykurnia/heroku-buildpack-ruby,jasonlevens/heroku-buildpack-ruby,instacart/heroku-buildpack-ruby,HYPERHYPER/heroku-buildpack-ruby,electricobjects/heroku-buildpack-ruby,crdschurch/heroku-buildpack-ruby,HYPERHYPER/heroku-buildpack-ruby,amaltson/heroku-buildpack-ruby,daltonrenaldo/heroku-buildpack-ruby,tomwolfe/heroku-buildpack-gsl-ruby,DouglasAllen/heroku-buildpack-ruby,samfrench/heroku-buildpack-ruby,anay/buildpack-ruby-with-oracle-jdk,ablease/custom-buildpack,hatofmonkeys/ruby-testing-buildpack,cmaggard/heroku-buildpack-turbo-sprockets,jumptvs/BP_Ruby,donnykurnia/heroku-buildpack-ruby,cloudn/buildpack-ruby,CPPWind/ruby-buildpack,hpcloud/ruby-buildpack,fcruxen/ruby-buildpack,cloudfoundry/ruby-buildpack,fgbreel/heroku-buildpack-ruby,markaschneider/heroku-buildpack-ruby-ffmpeg-sox,michaelphines/alexa-nest,icelab/heroku-buildpack-ruby,jayshreeanand/heroku-buildpack-ruby,gls1/heroku-buildpack-ruby-pdftk-new,0x00evil/heroku-buildpack-ruby,orenyk/heroku-buildpack-ruby,musicglue/heroku-buildpack-ruby,derrek/heroku-buildpack-ruby,bskyb-commerce/ruby-buildpack,takii/db2rubybuildpack,scottatron/moc-buildpack,mrhenry/heroku-buildpack-ruby,mattmanning/heroku-buildpack-ruby-jekyll,qnyp/heroku-buildpack-ruby-bower,vhx/heroku-buildpack,dlorson/gentle-buildpack,erintherad/heroku-buildpack-ruby,moneyadviceservice/heroku-buildpack-ruby-bowndler,redhotvengeance/heroku-buildpack-deep-thought,shuber/heroku-buildpack-ruby,lyoshenka/heroku-buildpack-ruby-jekyll,wakermahmud/heroku-buildpack-jekyll,Dim25/heroku-buildpack-ruby-GSL,blueapron/heroku-buildpack-ruby,qstream/heroku-buildpack-ruby,bskyb-commerce/ruby-buildpack,packetmonkey/heroku-buildpack-ruby,Nedomas/heroku-buildpack-ruby-minus-node-with-node-paths,CPPWind/ruby-buildpack,sstelfox/buildpack-ruby,DigitalInnovation/heroku-buildpack-mslabs,hpcloud/ruby-buildpack,derrek/heroku-buildpack-ruby,bellycard/heroku-buildpack-ruby,jgable/buildpack-ruby-rack-setup-tasks,amaltson/heroku-buildpack-ruby,gbenedict/heroku-buildpack-ruby,guidance-guarantee-programme/heroku-buildpack-princexml-old,ruby/heroku-buildpack-www-ruby-lang,andycroll/heroku-buildpack-jekyll,brightbytes/heroku-buildpack-ruby-without-assets-precompile,gls1/heroku-buildpack-ruby-pdftk,DyegoCosta/heroku-buildpack-ruby,Altoros/ruby-buildpack,CPPWind/ruby-buildpack,ndbroadbent/heroku-buildpack-turbo-sprockets,schu/buildpack-testing,KoanHealth/heroku-buildpack-marvin-setup,ndbroadbent/heroku-buildpack-turbo-sprockets,bskyb-commerce/help-heroku-buildpack,zidekmat/buildpack-ruby,fcruxen/ruby-buildpack,dlorson/gentle-buildpack,pietrop/heroku-buildpack-ruby,iamjarvo/ruby-buildpack,brightbytes/heroku-buildpack-ruby-without-assets-precompile,reesio/heroku-buildpack-ruby,d-reinhold/cf-buildpack-ruby,aarongray/heroku-buildpack-ruby,packetmonkey/heroku-buildpack-ruby,fgbreel/heroku-buildpack-ruby,cloudn/buildpack-ruby,jumptvs/BP_Ruby,ascot21/heroku-buildpack-turbo-sprockets,cmaggard/heroku-buildpack-turbo-sprockets,blueapron/heroku-buildpack-ruby,rowanoulton/heroku-buildpack-ruby,aarongray/heroku-buildpack-ruby,qnyp/heroku-buildpack-ruby-bower,sky-uk/help-heroku-buildpack,dieze/heroku-buildpack-ruby-hooks,cordata/heroku-buildpack-ruby,jumptvs/BP_Ruby,hixi/heroku-buildpack-ruby,mperejda/heroku-buildpack-ruby,mattwalters/heroku-buildpack-ruby,stefansundin/heroku-buildpack-ruby,space150/heroku-buildpack-ruby,schu/heroku-buildpack-ruby