Fixes #1359 by defaulting --heroku to a blank string instead of a nil which on some systems was putting 'heroku' instead.
Fixes #1359 by defaulting --heroku to a blank string instead of a nil which on some systems was putting 'heroku' instead.

simi/refinerycms,aguzubiaga/refinerycms,mojarra/myrefinerycms,mabras/refinerycms,kappiah/refinerycms,mkaplan9/refinerycms,anitagraham/refinerycms,mobilityhouse/refinerycms,trevornez/refinerycms,LytayTOUCH/refinerycms,hoopla-software/refinerycms,Retimont/refinerycms,chrise86/refinerycms,SmartMedia/refinerycms-with-custom-icons,stefanspicer/refinerycms,KingLemuel/refinerycms,mobilityhouse/refinerycms,simi/refinerycms,kappiah/refinerycms,stefanspicer/refinerycms,gwagener/refinerycms,louim/refinerycms,simi/refinerycms,johanb/refinerycms,gwagener/refinerycms,sideci-sample/sideci-sample-refinerycms,LytayTOUCH/refinerycms,refinery/refinerycms,mabras/refinerycms,anitagraham/refinerycms,Eric-Guo/refinerycms,KingLemuel/refinerycms,kelkoo-services/refinerycms,mojarra/myrefinerycms,refinery/refinerycms,kappiah/refinerycms,mlinfoot/refinerycms,louim/refinerycms,KingLemuel/refinerycms,Retimont/refinerycms,trevornez/refinerycms,LytayTOUCH/refinerycms,gwagener/refinerycms,mkaplan9/refinerycms,aguzubiaga/refinerycms,stefanspicer/refinerycms,bryanmtl/g-refinerycms,hoopla-software/refinerycms,bricesanchez/refinerycms,bryanmtl/g-refinerycms,hoopla-software/refinerycms,sideci-sample/sideci-sample-refinerycms,Retimont/refinerycms,SmartMedia/refinerycms-with-custom-icons,mlinfoot/refinerycms,mkaplan9/refinerycms,aguzubiaga/refinerycms,chrise86/refinerycms,anitagraham/refinerycms,Eric-Guo/refinerycms,kelkoo-services/refinerycms,trevornez/refinerycms,Eric-Guo/refinerycms,refinery/refinerycms,johanb/refinerycms,johanb/refinerycms,simi/refinerycms,mabras/refinerycms,chrise86/refinerycms,bricesanchez/refinerycms,mlinfoot/refinerycms