matplotlib Code

Move code for wrapping negative frequencies from specgram() into _spectral_helper(), so that psd(), csd(), and cohere() can benefit from this functionality as well. While this changes API a little, this is much more sensible behavior.

Fix the linespacing bug of multiline text (#1239682)

added fill_betweenx demo -- how did this get dropped from the original patch commit?

An optional offset and bbox support in restore_bbox

aspect for log-log plot

Clean up multiprocess a little. Remove unused import, ensure Gtk backend is used, and replace pylab with pyplot.

remove reserved word as from example

added examples/misc/rasterization_demo.py

Give a more descriptive name (multiprocess.py) to new example

Add an example of an updating plot using (multi)processing. Credit goes to Robert Cimrman.