Updated for Swift 1.1 literal convertible changes

I left the NSURL / StringLiteralConvertible section as is, since that isn't possible any more with the shift from static conversion methods to initializers. Sounds like they're working on a fix, but right now it's a no go: https://devforums.apple.com/message/1057358#1057358
Merge pull request #226 from natecook1000/patch-1

Updated for Swift 1.1 literal convertible changes