SciTools/cartopy — pull request #166 by pelson (2012-12-05 11:51:13+00:00)
Title: Worked around the NULL polygon issue raised by #152.

A workaround to avoid the heavy handed exception which was being raised by contouring some data.

This will have to go in *after* #126 as it requires a similar change to the ordering of the ```cartopy.config``` dictionary definition, but it would be nice to review this before that point.