working on guide for choosing colormaps. Have overview section and start on a few others.
added colormaps guide to beginner guide
some more text to colormaps
BUG : fix  _reshape_2D bug with [(n, 1), ..] input

cbook._reshape_2D the input can be _at most_ 2D, however if it
is passed a list of (n, 1) shaped ndarray this condition will
be violated and it fails to work (which is less than great, but
fine from a documentation stand point).  However, boxplot _used_
to work with a list of such ndarrays (and users might expect to
call a (n, 1) shaped array a 1D array).  The added `ravel` makes
sure that even if we get a list of any dimensional ndarrays in, the
output will be a list of (n, ) shaped arrays.

Closes #3220
Added 'double arrow' (DArrow) to patches.BoxStyle.
Added image test for arrow patches.

All bbox's in patches.BoxStyle are included in the test image.
Update patches doc and example.

Added Circle to annotations_guide.rst. Moved DArrow up so that entries
are sorted. Made fancybox_demo2.py outputs sorted box demo (so that
ordering matches annotations_guide). Increased spacing between boxes in
fancybox_demo2 to prevent overlap of images.
Quiver3d fixes

* numpy 1.6 does not support 3+ arguments for meshgrid
* actually use the sanitized data (fixes broadcasting issue)
* use argi through-out the function
* don't fail on zero flow, just don't draw a quiver
MNT : better error handling on determining gs version

If we fail to parse the version string return (0, 0) to let
the code for dealing with out-of-date versions of gs handle
the case of not installed.
added a bunch of stuff to my colormap info
Merge pull request #3284 from tacaswell/cbook_bxpstats_fix

BUG : fix  _reshape_2D bug with [(n, 1), ..] input
Merge pull request #3284 from tacaswell/cbook_bxpstats_fix

BUG : fix  _reshape_2D bug with [(n, 1), ..] input
Merge pull request #3300 from WeatherGod/mplot3d/quiver_test_fix

Quiver3d fixes
finished up draft
Merge pull request #3277 from tacaswell/gs_check

MNT : better error handling on determining gs version
Merge pull request #3194 from lkilcher/annotate_bbox_DArrow

Annotate bbox darrow
Check for GhostScript in this test which needs it
Merge pull request #3302 from jenshnielsen/checkdep_ghostscript

Check for GhostScript in this test which needs it
BUG : restore allow_rasterization on PolyCollection

The was accidentally removed as part of
b8726d09026ba7507d8501de0fbd921ec2d1243e

Closes #3299
Merge pull request #3306 from tacaswell/polycollection_allow_raster

BUG : restore allow_rasterization on PolyCollection