Fix W'bal in Train Performance Plot

.. code still needs to be refactored !
Plot W'bal on the fly in train mode

.. uses a fixed TAU of 300s so need to add some
   way of configuring it for on the fly calculations
Add W'bal TAU Config

.. it is only used in realtime mode
Placeholder for Moxy SandC cuckoo

.. the Moxy can be configured as a SandC sensor, so in
   readiness for ANT+ support in GC just adding code to
   spot it.

.. will also need to update this for when it is paired
   as a muscle oxygen monitor

.. will need to add SmO2 and tHb realtime data telemetry

.. will also need to add code to device config to notify
   when SandC is spotted as a moxy
Add HHb and O2Hb derived series

.. to split oxy/deoxy haemoglobin
.. need to add to ride chart too
O2Hb and HHb added to AllPlot Controls

.. now for the slog to add to the charts !
Add HHb and O2Hb to Allplot

.. so you can now look at oxy v deoxy as a time
   series against hr and power.
Train View Layout Update

.. show TSS and W' bal
.. reorganise to show realtime and performance plot
Gear Ratio - Coloring in PvPV plot

... option to show the datapoints depending on a gear ratio intervall
... gear-ratio 0 to 1 -> Red
... gear ratio 1.01 to 2.49 -> Yellow
... gear ratio 2.5 to 3.99 -> Green
... gear ratio 4 to max (7.00) -> Blue