Using a stricter check to see if Python was installed as a framework. Also, because of the recurring problems with non-framework Pythons, importing the Mac OS X backend will now fail (instead of just issuing a warning) if Python is not installed as a framework.
Closes issue #1593 - namespace error
Closes issue #1595 - sorting on a list of tuples can sometimes cause crashes
first pass at getting fixing Issue #1622
added unit test for zorder on hline and vline
removed redundant code

Do not need to explicitly call set_zorder because it gets done
in the call to coll.update.
Fixes #1630.  When callbacks were deleted, the cid map was not correctly updated.
pep8 compliance
fixed typo
Merge pull request #1628 from tacaswell/fix_errorbar_zorder_v1.2

Fix errorbar zorder v1.2
Added TriFinder and TrapezoidMapTriFinder classes.
Added LinearTriInterpolator class.
Improved PEP7 compliance.
Closes #1636.  When plotting a hexbin on a log scale, the "trick" to reuse the polygons can't work, so revert to the old method where each polygon is independent.
PEP8 fixes.
Seed the random number generator in the hexbin_log test
Merge pull request #1630 from mdboom/reconnect_callbacks

A disconnected callback cannot be reconnected
Merge pull request #1636 from mdboom/hexbin-log

hexbin log scale is broken in matplotlib 1.2.0
change cbook to relative import
Merge pull request #1618 from WeatherGod/mplot3d/crashfixes

Mplot3d/crashfixes