Also build sample project for 64-bit. This will expose any warnings related to 64-bit.
Cast UIControlState values to unsigned long and use the unsigned long string format specifier (%lu) when writing them to a string. NSUInteger is defined as unsigned int on 32-bit and unsigned long on 64-bit. This fix allows the code to build on 32- or 64-bit architectures without warnings.
If supporting only devices running iOS 7 or greater, use the sizeWithAttributes: method instead of the deprecated sizeWithFont: method. This removes the build warning that appears when only supporting iOS 7.
Tidy project groups.