Merge branch 'pcolorargs'
Merge pull request #2069 from jakevdp/anim_fix

BUG: pass kwargs to TimedAnimation
Merge pull request #2069 from jakevdp/anim_fix

BUG: pass kwargs to TimedAnimation
Merge branch 'pcolorargs'
Merge pull request #1975 from pwuertz/pgf_mixedrenderer

MixedModeRenderer non-72-dpi fixes & Pgf mixed rendering
Fix up error message about GObject introspection bindings
Merge pull request #1813 from mdboom/gtk3-version-check

GTK segfault with GTK3 and mpl_toolkits
Merge pull request #1813 from mdboom/gtk3-version-check

GTK segfault with GTK3 and mpl_toolkits
Merge pull request #2069 from jakevdp/anim_fix

BUG: pass kwargs to TimedAnimation
Merge branch 'v1.2.x' into v1.3.x
mlab.FIFOBuffer: remove fossil line referring to nonexistent method
Deprecate FIFOBuffer class
Version bump
use plt.subplots() in examples as much as possible

At the recent LBL Software Carpentry Workshop, it was pointed out that there's
an inconsistency within our documentation for how to create new figures with
subplots.

Indeed, most examples were using the old way, something like:

    fig = plt.figure()
    ax = plt.subplot(111) # or plt.add_subplot(111)

This patch changes a whole bunch of instances like the above to:

    fig, ax = plt.subplots()

We should strive to have a minimal amount of constants in our code,
especially unusual ones like `111`, which only make sense to Matlab
refugees.

I have left unchanged examples which were using axes keywords passed to
subplot() and add_subplot(), since those end up transforming things like:

    figure()
    subplot(111, axisbg='w')

to

    plt.subplots(subplot_kw=dict(axisbg='w'))

which isn't necessarily better.

I also did not touch most of the user_interfaces examples, since those did not
involve using plt, but instead explicitly imported Figure, and used the OO
approach on Figure instances.

Also updated instaces where the old "import pylab as p" convention was used to
use our standard "import matplotlib.pyplot as plt"

I have also updated some, but not all uses of subplot(121) etc, but I'm a bit
exhausted after doing all of these.
revert to OO interface (no pyplot) in OO example
more `subplots`, cleanup of old `import *` style
whats_new: a note about the changed examples
addressing PR feedback
Merge branch 'use-subplots' into v1.3.x
Merge remote-tracking branch 'upstream/v1.3.x'