matplotlib Code

Improve appearance of markers in Agg backend.

Fix compile for those that need the wxAgg C-extension.

Update TkAgg and GtkAgg extensions to match yesterday's refactoring in backend_agg

Reduce heap allocation of objects. Be safer when forced to do heap allocation. Remove some dead code.

Removed TODO (this has been implemented).

Remove empty "else" clause.

Remove unnecessary declaration.

Support reading low-bit depth (< 8) PNG images. Add PNG test suite to make sure we're supporting the basic kinds of PNG files available.

Add clip path support on images. Add a new example and update the dolphin fest.

updates to nxutils docstrings