It would be very useful if one could just supply an angle to create a rectangle patch rotated around it's center.
Would this just be for a rectangle, or for any arbitrary Patch object?
Hmmm, after doing a bit of fiddling, I think it'd be better to have this is a convenience method in mlab because the patch's transform can't be decided until an Axes object is created. See #1156.
Fixed in #1405.