RideEditor anomaly button enable/disable

.. if there are/aren't any anomalies in the ride.
Code Cleanup: CpintPlot Memory leak

.. kept allocating a new RideFileCache but didn't delete
the previous one. Given their relatively large size this
can lead large amounts of memory lost in a short amount
of time.
Merge branch 'master' of github.com:/GoldenCheetah/GoldenCheetah