Add quicklooks for new enterprise cloud mask variables
Quicklooks should be supported for the two new enterprise cloud mask variables (per FW2PUG#23).
Attached are the best example plots I could find, from a 2012 paper by Andy Heidinger, showing possible colorbars to use for a 4-level cloud mask and cloud probability. My initial thought was that the cloud mask should have a colorbar with discrete levels, but maybe there is value in having the mask on the same scale as probability since they are closely related.