matplotlib Code

Include output images in examples in documentation.
Add "-*- noplot -*-" markers to examples where we don't want that.
The "plot" documentation directive now takes a path relative to the doc/ directory, not doc/pyplots.

keep static figures with dynamically generated ones, but commit the
figures to svn so they will not be auto-generated. This way we can be
consistent in the way we include figures using the plot directive