.. User metrics can be created, deleted and edited
in the preferences pane.
.. A new dialog has been created to create user metrics
and will need to be updated after step 3 of this multi
part update completes the UserMetric code and integrates
it into the RideMetric factory.
.. User defined metrics where a user can define code
to compute a metric from ride data that can be used
in the same way as builtin metrics.
* Part 1 : Introduce User Metrics, Settings and XML config
* Part 2 : Introduce Dialog for User Metric CRUD in Preferences
* Part 3 : Integrate with Cache refresh and fingerprints
* Part 4 : Resolve dependency tree and related aspects
.. The user code will be via a DataFilter; this code has
already been updated to include variables, functions and
if/else/while constructs.
