Polygons and tissot across the edge in Mollweide:

There seems to be a known problem with `tissot` and `Polygon` in the 'Mollweide' projection with basemap when these objects cross the 'limb' (180 degree line if the central longitude is 0. which is both the East and West edges of the map). The obvious solution is of course to split this into two polygons split at the limb. I realized that this was actually already available in examples (for tissots):
https://github.com/matplotlib/basemap/blob/master/examples/allskymap.py
and am wondering if there are plans to eventually replace `Basemap.tissot` or if there are deeper problems with this.

Start with Basemap.tissot and Polygon handling for the Mollweide projection, then compare the existing tissot-related approach in examples/allskymap.py. Reproduce the case where an object crosses the limb and determine the expected behavior; the issue does not define a concrete acceptance condition beyond addressing the edge-crossing problem.

Written by the indexing model from the issue text.