REL: v3.3.2

This is the second bugfix release of the 3.3.x series.

This release contains several critical bug-fixes:

• fix Axis scale on twinned Axes
• fix auto-close of Figures in nbagg
• fix automatic title placement if Axes is off the Figure
• fix autoranging of log scales with barstacked histogram
• fix extra redraws when using Button or TextBox widgets
• fix imshow with LogNorm and large vmin/vmax ranges
• fix plotting Pandas DataFrame with string MultiIndex
• fix scatter with marker=''
• fix scatter3d color/linewidth re-projection
• fix state of mode buttons in TkAgg backends
• include license files in built distribution
• reduce Visual C++ runtime requirements on Windows