Revert "[stdlib] NSStringAPI: add stringByApplyingTransform"
Revert "[stdlib] NSStringAPI: add stringByApplyingTransform"

Right now this is breaking our iOS bots.  Let's temporarily revert while we investigate.

Swift SVN r28201

apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation