Do all color conversion in one place, reuse MPL methods
Test for QString, not QObject
Default to black if entered color is invalid
Update color button upon leaving lineedit, not while editing it
Clean up Qt objects from namespace
Added Examples section to `parse_yahoo_historical*`.

Fixed bug in `parse_yahoo_historical_ohlc`
fixed typos
updated `finance_demo.py` code to use new api
added the finance module to api list so the documentation gets
generated.
Bump minimum pyparsing version to 2.0.1, replace deprecated << with <<= and remove no longer relevant work around.
added depreciation warning to module doc-string

tweaked examples
cleaned up usage of `quotes_historical_yahoo` in demos
PEP8 on tri module source code.
PEP8 on tri* pylab_examples.
Correction to remove deprecation warning for plt.normalize.
Fix PyCXX check -- if import passes, we should assume that including it will also
Allow to set axes.grid.which in rcparams
Override stdout differently on Python 2 and 3
Merge pull request #2158 from magnunor/anchored_size_bar_height

Changes to anchored_artists.AnchoredSizeBar
Monkey patch pyparsing so that we can support pyparsing >= 1.5.6 on both Python 2 and 3 without loads of deprecation warnings.