Introduce ParseUtils as a cleaner way to parse hex or decimal strings to their...

Introduce ParseUtils as a cleaner way to parse hex or decimal strings to their primitive types. This is done instead of e.g. Integer.decode() in order to eliminiate the need to instantiate a new object wrapped around the primitive type if we're just going to use the primivitive type in the first place. Cleaned up all *Utils classes to use the new ParseUtils fuctions, which reduced a lot of duplicate code.