Add mutually exclusive bit to config

Add this mutually exclusive bit to the config,
and handle it properly in the other portions of
the rasptimer.  This doesnt do anything yet,
this will be handled in the next commit.
Implement mutually exclusive bit

If we are turning on a gpio pin that is mutually exclusive,
go through all the other pins that are also mutually
exclusive and turn them off first.  This helps in situations
where you have low speed and high speed for your motor
connected to different gpio pins and you want to make sure
you can't accidentally turn them both on at the same time.
Correctly display duration if it wraps around the day.

Correctly display the duration if we are wrapping around a
24-hour day.  Previously this showed negative durations.
The code now looks for negative end times and if they are
found it adds 24 to the hour.