Fixed memory leaks and modernised code

Added initWithCoder: method to SMFancyText.
Split SMFancyTextElement into separate file.
SMFancyText delegate method receives a pointer to the originating
object.
Modernised #pragmas.
Removed unnecessary property synthesizers.
Removed unnecessary private method signatures.
Replaced property calls in init and dealloc methods with calls to ivars.
All memory is correctly released.
Fixed compiler warnings about mismatched type comparisons.
Fixed compiler warnings about switched enum values.
Tidied up formatting.
Fixed newline warnings.
Added default retina image.