matplotlib Code

bug: xlim, ylim with no arguments should not affect autoscaling

backend_qt4.py: eliminate unnecessary import of Qt; closes [3108017]

bugfix: Collection.set_edgecolor was failing in mplot3d/contour_demo2

collections with color mapping: don't update rgba unnecesarily

PcolorImage: use local cache instead of the ScalarMappable.update_dict

image: more conversion to use rgba bytes, other minor cleanup

cbook.report_memory: add Windows support via "tasklist"

speed up Normalize, LogNorm, colormapping; modified patch by C. Gohlke

Image generation no longer generates double-precision rgba; patch by C. Gohlke

Image generation via color mapping was using doubles for rgba,
after which the _image module was converting rgba to uint8;
this patch saves time and memory by using the existing ability
of the colormap to generate uint8 directly.

Very basic first pass at rendering text using freetype-py http://code.google.com/p/freetype-py/