matplotlib Code

Rework the nan-handling/clipping/quantizing/simplification
framework so each is an independent part of a pipeline.
Expose the C++-implementation of all of this so it can be
used from all Python backends. Add rcParam
"path.simplify_threshold" to control the threshold of
similarity below which vertices will be removed.

Merged revisions 6827 via svnmerge from
https://matplotlib.svn.sf.net/svnroot/matplotlib/branches/v0_98_5_maint

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r6827 | mdboom | 2009-01-26 09:32:42 -0500 (Mon, 26 Jan 2009) | 2 lines

Make curves and NaNs play nice together
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Change simplification algorithm so it always returns points from the original data, rather than extrapolated ones. This is somewhat experimental.

Remove need for m_done flag in simlifier -- we can just put a path_stop onto the queue instead. Saves one boolean test on every iteration.

Use miter_join_revert in Agg backend to match behavior of other backends.

Bugfix of C typedef of MPL_Int64 failing on WinXP64

apply Michiel's patch to macosx backend to fix rounding bug - closes
sf bug 2508440.

applied michiel's hatch patch for macosx sf id 2497785

Add more hatch styles. Improve consistency across backends.

Fix path simplification by a) making it more conservative about when it will simplify based on segment length, and b) honoring path.simplify rcParam in Agg backend.