allow the new optional argument in _results methods
Following Charles Doutriaux's advice, delete a junk singleton axis correctly - so the mask is
preserved.  This will let LMWG display correctly - no pretense that values exist in the ocean.
Another variation on my test script.  This one tests the newgrid option to compute() or results().
Incorporate notes of advice from Charles D. on how to set colors in contour plots.
I'll try it out later.