added no_rot keyword
added no_rot parameter (only relevant for omerc projection)
renamed _geos to _geoslib, fixes for omerc
Applied Erik's right-click backend_bases fix
Fixed bugs in pcolorfast and in quadmesh rendering with svg, pdf
Fix bug in pcolorfast with single argument
committed eriks span selector patch
Improve colorbar handling of "hold" state
Make colorbar work regardless of "hold" state
applied stefans intro patch
