First attempt to implement RC6 Protocol

First attempt to implement RC6 Protocol

I've finally put together an implementation of the RC6 protocol.  The task
was made much easier by simply chucking the LIRC code and writing my own
implementation -- the LIRC system is just overly convoluted.  Alongside this,
the Philips keyset has finally been completed (along with keysets for
Magnavox and TiVo).  Also, I've done some general cleanup of the protocol
code.