Make plot_trisurf support custom triangulations

This brings plot_trisurf more inline with the 2d tri* method
equivalents. An example has also been added to: a) reflect the new
support; and b) illustrate the additional flexibility this change
enables.
Add the triangulation specification to dostring
Add comments to the example for clarity
Document that pcolormesh now takes a face argument to the edgecolor.
And clarify that the colorbar in axesgrid1 is also drawn with pcolormesh.
Merge pull request #1300 from jenshnielsen/pcolormesh_doc

Pcolormesh and colorbar documentation.
Update lib/mpl_toolkits/mplot3d/axes3d.py

Match argument names in error messages to argument names in documentation.
Update lib/mpl_toolkits/mplot3d/axes3d.py

Make Axes3D.scatter properly deal with `zs` being of size 1.
Merge pull request #1294 from jgehrcke/patch-1

Update lib/mpl_toolkits/mplot3d/axes3d.py
Update lib/mpl_toolkits/mplot3d/axes3d.py

Axes3D.scatter: raise exception in case z.size neither being 1 nor equaling x.size and y.size (according to documentation).
Update lib/mpl_toolkits/mplot3d/axes3d.py

Match argument names in error messages to argument names in documentation.
Update lib/mpl_toolkits/mplot3d/axes3d.py

Make Axes3D.scatter properly deal with `zs` being of size 1.
Use Objective C 1.0 [gs]etter
Merge pull request #1305 from dmcdougall/fix32bit

Fix pointer syntax error
Merge pull request #1285 from cgohlke/patch-12

Hide Tk root window until later
Hide Tk root window until later

On Windows, when using the tkagg backend with mpl 1.2.0rc2, before a figure window is displayed, a small, empty window is shown for a short amount of time.
Update ipython_directive.py for current versions of IPython
Attempt to fix image comparison on 32-bit platforms
Update version to 1.2.0rc2
Fixed to contour to support the _as_mpl_transform api.
Updated ContourSet api to make transform private (in favour of using a get_transform method).