Instead of just reimplementing the spreadsheet we now
implement according to the original formulas as defined
in the W'bal paper.
This means there is no longer a 1200s limit to the decay
which was not part of the original paper.
We should be able to add some W'bal metrics now.
Added auto finding matches in Wprime, but there are
two areas to develop further;
1. Use the W'bal data to find matches instead of the
power above CP (which is really being used as a proxy
for the better approach).
2. Update the 'find intervals' dialog to allow you to
find matches and add them as normal intervals.
Pushing to repo as a version checkpoint, this function
will definitely need refining before 3.1 is released.
In preferences->athlete->power you can now set
your W' in joules alongside your CP.
This is also available in the new cyclist dialog
which also defaults to 20Kj.
Fix 1s smoothing to ensure time doesn't go backwards
as when the same timestamp is used more than once the
QwtSpline used to interpolate returns all zeroes.
The implementation set tau to a constant when it
should be derived from the recovery power across
the ride.
I've also added tau to the chart so you can see
what value has been derived.
It TREBLES the amount of time required to refresh the
metrics, so will need to be optmised before 3.1 is released.
But it should only need to run once.
I've also added a 'RideMetric::Low' type which we could
also apply to weight.
