matplotlib Code

Update examples and skeletons in py4science.

- Fixes after previous feedback so they are all syntactically correct.

- Switch to using nose instead of unittest for an eaiser workflow.

improved interactive pan/zoom in qt4agg backend on windows

Fix bug introduced in 6033, reported by Jae-Joon Lee

another minor tweak

minor tweaks

update

added cubed_sphere.py example

added install instructions to new docs

Remove deprecated Numpy call.

[ 2029956 ] Fix documentation warnings.