Kill dead dangling num_sources docs. (#4655)
Kill dead dangling num_sources docs. (#4655)

A partial removal happened in 1c7de069.
pantsbuild/pants,fkorotkov/pants,foursquare/pants,fkorotkov/pants,baroquebobcat/pants,baroquebobcat/pants,15Dkatz/pants,15Dkatz/pants,baroquebobcat/pants,UnrememberMe/pants,UnrememberMe/pants,15Dkatz/pants,baroquebobcat/pants,benjyw/pants,15Dkatz/pants,benjyw/pants,twitter/pants,landism/pants,twitter/pants,UnrememberMe/pants,twitter/pants,tdyas/pants,foursquare/pants,baroquebobcat/pants,wisechengyi/pants,tdyas/pants,foursquare/pants,wisechengyi/pants,landism/pants,15Dkatz/pants,baroquebobcat/pants,UnrememberMe/pants,pantsbuild/pants,twitter/pants,baroquebobcat/pants,twitter/pants,jsirois/pants,landism/pants,pantsbuild/pants,benjyw/pants,benjyw/pants,tdyas/pants,benjyw/pants,foursquare/pants,foursquare/pants,fkorotkov/pants,landism/pants,UnrememberMe/pants,twitter/pants,15Dkatz/pants,tdyas/pants,tdyas/pants,wisechengyi/pants,pantsbuild/pants,landism/pants,benjyw/pants,wisechengyi/pants,tdyas/pants,jsirois/pants,foursquare/pants,pantsbuild/pants,wisechengyi/pants,foursquare/pants,baroquebobcat/pants,tdyas/pants,twitter/pants,landism/pants,fkorotkov/pants,pantsbuild/pants,wisechengyi/pants,15Dkatz/pants,15Dkatz/pants,landism/pants,landism/pants,UnrememberMe/pants,UnrememberMe/pants,wisechengyi/pants,foursquare/pants,fkorotkov/pants,fkorotkov/pants,twitter/pants,baroquebobcat/pants,fkorotkov/pants,UnrememberMe/pants,tdyas/pants,tdyas/pants,pantsbuild/pants,benjyw/pants,foursquare/pants,wisechengyi/pants,jsirois/pants,twitter/pants,wisechengyi/pants,UnrememberMe/pants,fkorotkov/pants