Move from github to bintray for pants support binaries.
Move from github to bintray for pants support binaries.

Reviewed at https://reviews.apache.org/r/27114/

apache/aurora,thinker0/aurora,wfarner/aurora,rdelval/aurora,thinker0/aurora,rosmo/aurora,crashlytics/aurora,crashlytics/aurora,protochron/aurora,rosmo/aurora,protochron/aurora,mschenck/aurora,thinker0/aurora,kidaa/aurora,crashlytics/aurora,medallia/aurora,crashlytics/aurora,mschenck/aurora,kidaa/aurora,shahankhatch/aurora,protochron/aurora,shahankhatch/aurora,apache/aurora,rosmo/aurora,kidaa/aurora,protochron/aurora,medallia/aurora,medallia/aurora,rosmo/aurora,mschenck/aurora,shahankhatch/aurora,protochron/aurora,kidaa/aurora,crashlytics/aurora,thinker0/aurora,rdelval/aurora,rdelval/aurora,apache/aurora,mschenck/aurora,kidaa/aurora,kidaa/aurora,apache/aurora,thinker0/aurora,rosmo/aurora,rosmo/aurora,apache/aurora,mschenck/aurora,wfarner/aurora,rdelval/aurora,thinker0/aurora,mschenck/aurora,apache/aurora,rdelval/aurora,wfarner/aurora,shahankhatch/aurora,shahankhatch/aurora,shahankhatch/aurora,crashlytics/aurora,rdelval/aurora,protochron/aurora,wfarner/aurora,wfarner/aurora,medallia/aurora,wfarner/aurora,medallia/aurora,medallia/aurora