added debug checks.  Disable slaveTimer if TIME_INFINITE timeout.  Builds w/o I2C_SLAVE
Allow zero length writes
Cleaned up typecasts on masks.  Abort now preserves controller address matching.
removed I2C_BUSY bit from event mask
hacked to ignore sprious events for master transmit
Added chVTInit to explicitly initialize timers into their "disarmed" state
Explicitly initialize VTimers to their disarmed state.

Added debug facility for recording I2C event masks.
added protocol parsing state transition checks

added master low-level processing modes
Improved I2C Master API debug assertion logic