Working with binary values and hexadecimal values using the bit array library

[mattbornski]

Javascript bit manipulation functions have trouble with large numbers; your library makes it much easier! Unfortunately many of the formulas and constants used in such manipulations are expressed in hex. I've added a few functions and tests to make converting to/from hex representations easier in your library.

[bramstein]

Thanks, I've been meaning to do this for a while. Also thanks for fixing the tests :)