Rename LICENSE.md to LICENSE

LICENSE.md should be LICENSE. CocoaPods currently throws an error:

[!] Unable to read the license file `/Users/jbowen/Code/ios/Buddy Quote/Pods/NSDate-Time-Ago/LICENSE` for the spec `NSDate-Time-Ago (1.0)`

See http://guides.cocoapods.org/making/making-a-cocoapod.html.