Radically reduce first run pod setup bandwidth.

Given that Cocoapods doesn't need the history of the Specs repo we can radically improve the initial setup time by only checking out HEAD. This reduces the initial download from >200MB to roughly 3.5MB, a massive win for folks with slow interwebs.

git pull/git fetch+git rebase work as expected.

Those bades look much nicer than the PNG badges on retina displays.

Add test for lint failures

Updated guidelines on submitting feature requests

Improve the lockfile version warning message

Correct a typo and improve the warning message that's shown when the
lock file was created with a newer version of CocoaPods.

Add tests for the spec edit command

Clarify author documentation and template

See https://github.com/CocoaPods/Xcodeproj/commit/0704b7772370feb8be154ace0ce48e09f215aeaf.

Merge branch 'newcommandspec' of https://github.com/carsonmcdonald/CocoaPods into carsonmcdonald-newcommandspec

Conflicts:
	spec/spec_helper/user_interface.rb

README update to refer to guides.