Allow the specification of a source URL in a Podfile
Make the specification of URL in Podfile much more robust
[Documentation] Clarify what Analyzer#sources returns
[AnalyzerSpec] Use # when describing a single method
[SourcesManager] Dont use modifier unless on monster raise statement.

Thanks @k0nserv!
[SourcesManagerSpec] Make it clearer that #source_with_url returns something.

Thanks @mrackwitz!
[Changelog] Add entry about specifying sources in the Podfile by URL
[Gemfile] Return to Core master branch
[Changelog] Update wording of Podfile sources entry

Thanks @orta
[SourcesManager] Make searching for a source via URL case-insensitive
Merge pull request #2513 from CocoaPods/podfile-source-url

Allow the specification of a source URL in a Podfile