Split up master and slave routines into different files for i2c module.  Unified the buffers used by the master and slave mib routines
in mib_state.  The slave logic now disables the master logic once it receives a valid address and reenables it after it finishes receiving a command
MIB protocol code is at a useable level.  The packet layer checks each packet for checksum errors and informs
the rpc layer.  The rpc layer is robust against transient errors.  It automatically resends commands and parameters
and return values until they are properly received.  I need to add checking for nonexistant slaves since currently
we would just loop forever in that case since their response checksums would never match up.

The code should be pretty stable at this point though and I envision relatively minor changes to it from now on.