Two comm modes need to be consolidated.

The two communication modes (uplink LF=640kHz and uplink LF=160kHz) represented by the '640kHz' branch and 'master' branch, respectively, need to be consolidated. It is increasingly unwieldy to keep them alive in separate branches, and therefore both users and developers could benefit from consolidation.

I propose that we have the WISP automatically choose a mode based on the reader's requested protocol spec in the Query command. This shouldn't be a tremendously difficult task. For simple clock adjust routines, use of function pointers may help simplify the implementation of a multiprotocol WISP. Most everything else falls into place with a simple clock adjustment for switching btwn these two protocols.