Make it easier to request another ReviewBot run, and flag diffs that seem to lack test coverage.
Make it easier to request another ReviewBot run, and flag diffs that seem to lack test coverage.

Reviewed at https://reviews.apache.org/r/27770/

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