Fix SEGV on CP export with no model
Add TSS per hour metric

.. on request from Massarob.
Pedalling metrics, ignore zeroes in Average

.. when averaging lr balance, pedal smoothness etc we now
   ignore values when cadence is zero.

.. the zero values are not meaningful and skew the average to
   render them almost useless !
Add Group By ALL to LTM

.. can see the total / average or bests for the date range selected

NOTE: Data Table mode is currently a bit broken .. need to revisit it
      and fix it up, not just for ALL mode but also for Estimates
Sidebar summary honor color changes

.. was not being redrawn when the color preferences changed.
Merge remote-tracking branch 'upstream/master'