[Gitignore] Add documentation folder
[Podfile] Added sources array
[AggregateTarget] Support for directory list
[Podfile] Documentation
[Source::Aggregate] Style & Documentation
[Lockfile] Return multiple dependencies to lock a Pod

See https://github.com/CocoaPods/CocoaPods/pull/2297
Merge pull request #160 from CocoaPods/fabio/specs-sources

0.34 rc