matplotlib Code

Fix that imdenoise tries to slice into the gray-level moonlanding image as
if it were color.

Fix contributed by Stefan van der Walt.

Cleanup and updates to many examples.

Added new tool to create skeletons and solutions from a single source
script.

Update examples and skeletons in py4science.

- Fixes after previous feedback so they are all syntactically correct.

- Switch to using nose instead of unittest for an eaiser workflow.

Add agenda for 2008 SciPy tutorial, plus misc. updates to scripts.

reor and fix pyrex examples