[Rakefile] Improvements to gem:release.
[Rakefile] Improvements to gem:release.

segiddins/CocoaPods,mglidden/CocoaPods,orta/CocoaPods,mglidden/CocoaPods,vivekshukla-mob-ibtech/Repository,0xced/CocoaPods,ashfurrow/CocoaPods,Ashton-W/CocoaPods,mglidden/CocoaPods