Implemented fix to issue 196 on github for log=True and histtype='step'
fixed the minimum specification in ax.hist as per @WeatherGod's comment;
only want to set min this way if log is specified.  Also, added case for
normed vs not
Use numpy.min
Add hist step log test
Use actual log base, instead of assuming a default
Enable to switch off the removal of comments in csv2rec.
PEP8
[ENH] added baseline feature to stacked graph.
pep8 compliance
Fix typos
Add stackplot baseline demo
Update changelog and whats_new
Add stackplot baseline test
Remove text from regression test output
Vectorise the loops

This boasts an O(10^4) speed up
Add docstring to example funtion

Also made a minor PEP8 change
Merge pull request #1678 from tacaswell/qt4_closeevent

added QtGui.QMainWindow.closeEvent() to make sure the close event
Re-wired signal/slot connections so that the figure in removed from
Gcf when it is closed.

In PR #1498 the attribute WA_DeleteOnClose was no longer set on the
QtMainWindow object in QtFigureManager.  The signal connection that
was being used to remove the figure from Gcf when the window was closed
was tied to the `destroyed()` signal of QtMainWindow, which is no
longer being destroyed.  Thus, gca and gcf would return references
to no-longer visible figures/axes.  _widgetclosed is now called when
MainWindow emits 'closing()'.
PEP8: whitespaces
Add figure close test for qt4 backend