Bump minimum pyparsing version to 2.0.1, replace deprecated << with <<= and remove no longer relevant work around.
Monkey patch pyparsing so that we can support pyparsing >= 1.5.6 on both Python 2 and 3 without loads of deprecation warnings.
Install latest version of pyparsing
Exclude use of pyparsing 2.0.0 everywhere
Merge pull request #1 from mdboom/pyparsing-monkey-patch

Pyparsing monkey patch
Use absolute import so we don't accidentally import the old pyparsing from matplotlib 1.1.1 (or earlier) if it's still around in the user's site-packages.
Use gswin64c, if found.
Merge pull request #2279 from jenshnielsen/pyparsing

Pyparsing
Merge pull request #2290 from selasley/master

Fix a recursion problem with masked arrays in get_converter
Conflicts:
	lib/matplotlib/units.py
Disable core pdf font test on TRAVIS
Make pyplot.bar color kwarg less ambiguous
Merge pull request #2266 from mdboom/fix-pyparsing-cruft

pyparsing version parsing error
Merge pull request #2278 from mdboom/gs-win64c

Can't find 64-bit GhostScript on win64
fix the docstring for scale_docs to only strip whitespace at the end (the whitespace at the beginning is needed for alignment)
make all optional backends respect the cfg file
except AttributeError in module gi during checking for gtk3 backends
Merge pull request #2308 from dmcdougall/v1.2.x

Make pyplot.bar color kwarg less ambiguous
Fix #2338: pyparsing in 1.5.7's <<= operator doesn't return self, so we need to monkey patch it, too
Merge pull request #2344 from anshbansal/master

Fixed the issue of pyplot tutorial missing the show() command
Merge pull request #2334 from andreabedini/patch-4

Remove disabled code.