Minor updates to inheritance diagram.
fixed a couple typos in artists.rst
minor cleanup in documentation guide
Add some range checking based on testing in Fusil.
Bugfix: crash displaying fontconfig pattern
[ 2013963 ] update_datalim_bounds in Axes not works
[ 2014183 ] multiple imshow() causes gray edges
added tmerc and cass examples
Fix rectangular polar axes patch (continued...)
Fix rectangular polar axes patch.
