testing: move test/mplTest/units to lib/matplotlib/testing/jpl_units
testing: baseline images now in svn. specify image names without '.png'
testing: set backend to Agg only once
testing: move baseline image
fix the test_date images
fix to empty datetime bug; add datetime tests
docs: describe how to run tests
testing: add matplotlib.test() function to run tests
testing: remove leftover files from past image comparison failures
add dyld to mac osx file
