Raise a better error message when testing_support/common_rake can't be found
Raise a better error message when testing_support/common_rake can't be found

Fixes #2041

Ropeney/spree,gautamsawhney/spree,jparr/spree,dandanwei/spree,jspizziri/spree,carlesjove/spree,richardnuno/solidus,edgward/spree,Senjai/spree,karlitxo/spree,Boomkat/spree,StemboltHQ/spree,lsirivong/solidus,JDutil/spree,rbngzlv/spree,firman/spree,sideci-sample/sideci-sample-spree,carlesjove/spree,vinayvinsol/spree,pervino/solidus,KMikhaylovCTG/spree,orenf/spree,delphsoft/spree-store-ballchair,priyank-gupta/spree,nooysters/spree,assembledbrands/spree,Kagetsuki/spree,DynamoMTL/spree,gregoryrikson/spree-sample,robodisco/spree,sliaquat/spree,ayb/spree,caiqinghua/spree,kitwalker12/spree,tomash/spree,agient/agientstorefront,progsri/spree,mleglise/spree,Engeltj/spree,jspizziri/spree,mindvolt/spree,jsurdilla/solidus,Mayvenn/spree,jhawthorn/spree,RatioClothing/spree,shekibobo/spree,locomotivapro/spree,gregoryrikson/spree-sample,keatonrow/spree,project-eutopia/spree,alejandromangione/spree,groundctrl/spree,Senjai/solidus,Hawaiideveloper/shoppingcart,Nevensoft/spree,rakibulislam/spree,Senjai/spree,imella/spree,nooysters/spree,softr8/spree,azclick/spree,alejandromangione/spree,grzlus/spree,alvinjean/spree,Senjai/solidus,bricesanchez/spree,keatonrow/spree,brchristian/spree,urimikhli/spree,miyazawatomoka/spree,patdec/spree,edgward/spree,lsirivong/spree,Lostmyname/spree,kewaunited/spree,wolfieorama/spree,Kagetsuki/spree,rbngzlv/spree,Machpowersystems/spree_mach,Machpowersystems/spree_mach,orenf/spree,reinaris/spree,omarsar/spree,caiqinghua/spree,surfdome/spree,wolfieorama/spree,Antdesk/karpal-spree,zaeznet/spree,progsri/spree,odk211/spree,delphsoft/spree-store-ballchair,berkes/spree,NerdsvilleCEO/spree,alejandromangione/spree,vinayvinsol/spree,jasonfb/spree,LBRapid/spree,groundctrl/spree,berkes/spree,trigrass2/spree,tancnle/spree,jordan-brough/spree,grzlus/spree,Antdesk/karpal-spree,APohio/spree,sliaquat/spree,DynamoMTL/spree,omarsar/spree,firman/spree,lzcabrera/spree-1-3-stable,vmatekole/spree,njerrywerry/spree,caiqinghua/spree,yiqing95/spree,TimurTarasenko/spree,dandanwei/spree,tancnle/spree,degica/spree,beni55/spree,orenf/spree,Arpsara/solidus,jspizziri/spree,ahmetabdi/spree,Migweld/spree,radarseesradar/spree,jimblesm/spree,richardnuno/solidus,codesavvy/sandbox,scottcrawford03/solidus,pervino/spree,net2b/spree,moneyspyder/spree,grzlus/solidus,hifly/spree,surfdome/spree,bjornlinder/Spree,StemboltHQ/spree,zaeznet/spree,surfdome/spree,sunny2601/spree,ahmetabdi/spree,bonobos/solidus,zaeznet/spree,reinaris/spree,bricesanchez/spree,progsri/spree,robodisco/spree,CiscoCloud/spree,lyzxsc/spree,jordan-brough/solidus,TrialGuides/spree,firman/spree,imella/spree,lzcabrera/spree-1-3-stable,alejandromangione/spree,Ropeney/spree,rbngzlv/spree,lyzxsc/spree,watg/spree,firman/spree,lyzxsc/spree,mleglise/spree,dafontaine/spree,assembledbrands/spree,SadTreeFriends/spree,APohio/spree,judaro13/spree-fork,ckk-scratch/solidus,project-eutopia/spree,AgilTec/spree,CiscoCloud/spree,azranel/spree,welitonfreitas/spree,sunny2601/spree,woboinc/spree,archSeer/spree,omarsar/spree,jordan-brough/solidus,bonobos/solidus,dotandbo/spree,azclick/spree,lsirivong/spree,knuepwebdev/FloatTubeRodHolders,athal7/solidus,archSeer/spree,moneyspyder/spree,patdec/spree,PhoenixTeam/spree_phoenix,volpejoaquin/spree,shioyama/spree,thogg4/spree,beni55/spree,sliaquat/spree,CJMrozek/spree,calvinl/spree,hifly/spree,jparr/spree,miyazawatomoka/spree,ckk-scratch/solidus,njerrywerry/spree,dafontaine/spree,watg/spree,bonobos/solidus,ckk-scratch/solidus,kewaunited/spree,useiichi/spree,trigrass2/spree,richardnuno/solidus,sfcgeorge/spree,ramkumar-kr/spree,jasonfb/spree,jaspreet21anand/spree,forkata/solidus,yiqing95/spree,shaywood2/spree,vinsol/spree,kitwalker12/spree,CiscoCloud/spree,Hawaiideveloper/shoppingcart,DarkoP/spree,jimblesm/spree,shioyama/spree,tailic/spree,SadTreeFriends/spree,project-eutopia/spree,grzlus/solidus,Antdesk/karpal-spree,wolfieorama/spree,PhoenixTeam/spree_phoenix,ujai/spree,miyazawatomoka/spree,maybii/spree,volpejoaquin/spree,APohio/spree,jordan-brough/spree,knuepwebdev/FloatTubeRodHolders,rajeevriitm/spree,vcavallo/spree,athal7/solidus,ahmetabdi/spree,jsurdilla/solidus,sideci-sample/sideci-sample-spree,hoanghiep90/spree,madetech/spree,Engeltj/spree,robodisco/spree,codesavvy/sandbox,RatioClothing/spree,kitwalker12/spree,yiqing95/spree,DarkoP/spree,camelmasa/spree,vinsol/spree,archSeer/spree,useiichi/spree,pervino/solidus,delphsoft/spree-store-ballchair,ramkumar-kr/spree,pulkit21/spree,lyzxsc/spree,kewaunited/spree,camelmasa/spree,KMikhaylovCTG/spree,moneyspyder/spree,jhawthorn/spree,net2b/spree,madetech/spree,derekluo/spree,useiichi/spree,urimikhli/spree,patdec/spree,brchristian/spree,trigrass2/spree,pjmj777/spree,hoanghiep90/spree,derekluo/spree,freerunningtech/spree,codesavvy/sandbox,azranel/spree,raow/spree,derekluo/spree,cutefrank/spree,ckk-scratch/solidus,maybii/spree,watg/spree,urimikhli/spree,DarkoP/spree,shekibobo/spree,Machpowersystems/spree_mach,alvinjean/spree,piousbox/spree,degica/spree,SadTreeFriends/spree,cutefrank/spree,hifly/spree,Kagetsuki/spree,camelmasa/spree,ramkumar-kr/spree,Senjai/spree,vulk/spree,locomotivapro/spree,moneyspyder/spree,TrialGuides/spree,dafontaine/spree,Lostmyname/spree,Arpsara/solidus,HealthWave/spree,JuandGirald/spree,tesserakt/clean_spree,jparr/spree,woboinc/spree,AgilTec/spree,KMikhaylovCTG/spree,karlitxo/spree,bricesanchez/spree,PhoenixTeam/spree_phoenix,jeffboulet/spree,archSeer/spree,siddharth28/spree,shekibobo/spree,vinayvinsol/spree,vmatekole/spree,jimblesm/spree,athal7/solidus,Kagetsuki/spree,agient/agientstorefront,zamiang/spree,Hates/spree,lsirivong/solidus,JuandGirald/spree,reidblomquist/spree,dotandbo/spree,shioyama/spree,volpejoaquin/spree,alepore/spree,azclick/spree,devilcoders/solidus,shekibobo/spree,kewaunited/spree,sideci-sample/sideci-sample-spree,judaro13/spree-fork,Migweld/spree,forkata/solidus,tomash/spree,NerdsvilleCEO/spree,scottcrawford03/solidus,dandanwei/spree,jordan-brough/spree,assembledbrands/spree,Migweld/spree,biagidp/spree,joanblake/spree,Hawaiideveloper/shoppingcart,useiichi/spree,FadliKun/spree,jhawthorn/spree,PhoenixTeam/spree_phoenix,delphsoft/spree-store-ballchair,sfcgeorge/spree,Arpsara/solidus,siddharth28/spree,quentinuys/spree,mleglise/spree,tesserakt/clean_spree,adaddeo/spree,xuewenfei/solidus,brchristian/spree,carlesjove/spree,bjornlinder/Spree,ayb/spree,Engeltj/spree,hoanghiep90/spree,cutefrank/spree,Nevensoft/spree,madetech/spree,raow/spree,fahidnasir/spree,raow/spree,bonobos/solidus,NerdsvilleCEO/spree,Ropeney/spree,jordan-brough/solidus,builtbybuffalo/spree,jaspreet21anand/spree,brchristian/spree,ujai/spree,fahidnasir/spree,ramkumar-kr/spree,mleglise/spree,jspizziri/spree,net2b/spree,surfdome/spree,gregoryrikson/spree-sample,pjmj777/spree,tailic/spree,jasonfb/spree,dotandbo/spree,shaywood2/spree,shaywood2/spree,HealthWave/spree,yomishra/pce,maybii/spree,Mayvenn/spree,jaspreet21anand/spree,madetech/spree,odk211/spree,jasonfb/spree,thogg4/spree,thogg4/spree,wolfieorama/spree,FadliKun/spree,vulk/spree,TrialGuides/spree,devilcoders/solidus,lsirivong/spree,softr8/spree,hoanghiep90/spree,omarsar/spree,ujai/spree,ahmetabdi/spree,codesavvy/sandbox,grzlus/spree,project-eutopia/spree,pulkit21/spree,radarseesradar/spree,yushine/spree,azclick/spree,rbngzlv/spree,Hates/spree,adaddeo/spree,tancnle/spree,hifly/spree,Ropeney/spree,Mayvenn/spree,Senjai/solidus,gautamsawhney/spree,piousbox/spree,vulk/spree,robodisco/spree,keatonrow/spree,abhishekjain16/spree,abhishekjain16/spree,NerdsvilleCEO/spree,fahidnasir/spree,odk211/spree,Hawaiideveloper/shoppingcart,biagidp/spree,judaro13/spree-fork,richardnuno/solidus,reinaris/spree,joanblake/spree,vmatekole/spree,patdec/spree,jaspreet21anand/spree,sfcgeorge/spree,siddharth28/spree,agient/agientstorefront,jimblesm/spree,dotandbo/spree,CiscoCloud/spree,sunny2601/spree,FadliKun/spree,knuepwebdev/FloatTubeRodHolders,alvinjean/spree,adaddeo/spree,pulkit21/spree,mindvolt/spree,scottcrawford03/solidus,Nevensoft/spree,calvinl/spree,mindvolt/spree,yushine/spree,tesserakt/clean_spree,nooysters/spree,lsirivong/spree,net2b/spree,Boomkat/spree,jeffboulet/spree,pervino/spree,fahidnasir/spree,edgward/spree,xuewenfei/solidus,builtbybuffalo/spree,yushine/spree,forkata/solidus,thogg4/spree,vcavallo/spree,TrialGuides/spree,devilcoders/solidus,Arpsara/solidus,vulk/spree,rakibulislam/spree,JuandGirald/spree,zaeznet/spree,sunny2601/spree,berkes/spree,RatioClothing/spree,njerrywerry/spree,grzlus/solidus,yomishra/pce,welitonfreitas/spree,woboinc/spree,TimurTarasenko/spree,FadliKun/spree,edgward/spree,radarseesradar/spree,vinsol/spree,priyank-gupta/spree,ayb/spree,Mayvenn/spree,rakibulislam/spree,jeffboulet/spree,keatonrow/spree,Migweld/spree,lzcabrera/spree-1-3-stable,orenf/spree,rajeevriitm/spree,calvinl/spree,grzlus/solidus,Engeltj/spree,softr8/spree,tomash/spree,alepore/spree,ayb/spree,quentinuys/spree,Lostmyname/spree,KMikhaylovCTG/spree,JDutil/spree,Boomkat/spree,Senjai/solidus,Boomkat/spree,jparr/spree,carlesjove/spree,gautamsawhney/spree,derekluo/spree,grzlus/spree,AgilTec/spree,DynamoMTL/spree,gregoryrikson/spree-sample,JDutil/spree,beni55/spree,bjornlinder/Spree,groundctrl/spree,freerunningtech/spree,cutefrank/spree,SadTreeFriends/spree,berkes/spree,vcavallo/spree,Hates/spree,progsri/spree,gautamsawhney/spree,imella/spree,priyank-gupta/spree,dandanwei/spree,forkata/solidus,rajeevriitm/spree,karlitxo/spree,LBRapid/spree,Nevensoft/spree,yiqing95/spree,jordan-brough/solidus,tomash/spree,builtbybuffalo/spree,quentinuys/spree,joanblake/spree,athal7/solidus,reinaris/spree,maybii/spree,yomishra/pce,reidblomquist/spree,pulkit21/spree,builtbybuffalo/spree,devilcoders/solidus,reidblomquist/spree,Lostmyname/spree,lsirivong/solidus,AgilTec/spree,xuewenfei/solidus,StemboltHQ/spree,pervino/solidus,priyank-gupta/spree,odk211/spree,locomotivapro/spree,alvinjean/spree,pervino/spree,alepore/spree,tancnle/spree,joanblake/spree,welitonfreitas/spree,locomotivapro/spree,beni55/spree,xuewenfei/solidus,DynamoMTL/spree,adaddeo/spree,shaywood2/spree,APohio/spree,mindvolt/spree,dafontaine/spree,CJMrozek/spree,pervino/solidus,rakibulislam/spree,azranel/spree,vmatekole/spree,CJMrozek/spree,pjmj777/spree,radarseesradar/spree,calvinl/spree,JDutil/spree,tailic/spree,camelmasa/spree,CJMrozek/spree,vinsol/spree,rajeevriitm/spree,jsurdilla/solidus,jsurdilla/solidus,piousbox/spree,LBRapid/spree,vcavallo/spree,HealthWave/spree,abhishekjain16/spree,miyazawatomoka/spree,azranel/spree,karlitxo/spree,lsirivong/solidus,TimurTarasenko/spree,abhishekjain16/spree,tesserakt/clean_spree,nooysters/spree,reidblomquist/spree,agient/agientstorefront,biagidp/spree,zamiang/spree,vinayvinsol/spree,softr8/spree,jeffboulet/spree,trigrass2/spree,sliaquat/spree,volpejoaquin/spree,zamiang/spree,siddharth28/spree,quentinuys/spree,degica/spree,njerrywerry/spree,yushine/spree,raow/spree,caiqinghua/spree,DarkoP/spree,zamiang/spree,JuandGirald/spree,TimurTarasenko/spree,pervino/spree,groundctrl/spree,freerunningtech/spree,scottcrawford03/solidus,piousbox/spree,welitonfreitas/spree,sfcgeorge/spree,Hates/spree