Suppress some warnings in Xcode

In my pull request I fixed 2 errors:

1. UIView+FLKAutoLayout.m:240:28: Implicit conversion loses floating-point precision: 'double' to 'CGFloat' (aka 'float')
2. UIView+FLKAutoLayoutPredicate.h:18:31: Unused function 'FLKAutoLayoutPredicateMake'