User configurable data entry for recording information about
each workout.
FEATURES:
* Config UI for defining tabs and fields to maintain
* Config UI for defining keywords and colors
* Data maintenance UI on RideSummaryWindow
* "Special" Metadata fields are related to current variables
* Read/Write new fields/metric overrides via GcRideFile
* Metadata extraction in WKO files
* Calendar uses keyword and color config
* Numeric metadata is plottable on the Metric charts
*Metric refresh has been optimised
