Fixed warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
Fixed fields initialization order warnings [-Wreorder]
Fixed warning: comparison of integers of different signs [-Wsign-compare]
Fixed warning: auto property synthesis is synthesizing property not explicitly synthesized [-Wobjc-missing-property-synthesis]
Fixed warning: weak instance variable '_delegate' is accessed multiple times in this method but may be unpredictably set to nil; assign to a strong variable to keep the object alive [-Warc-repeated-use-of-weak]
Added more compilation warnings.
Fixed auto property synthesis for POP tests.
Removed unused header.
Fixed more warning: comparison of integers of different signs.
Added missing methods definition.
Fixed CGFloat to double conversion when interpolating basic animations.
Fixed typo.
Merge pull request #102 from jcbertin/master

Fixed miscellaneous warnings.