first version of export_pickle, tests need fixing
fix mocking (we now use __builtin__.open)
menpo.io.input.base moved to use pathlib
remove redundent methods (should be in menpo3d)
pickle importing added
added docs for pickling
flip export methods args to (obj, fp)-match pickle
add pickle unit tests
Merge pull request #521 from jabooth/export_pickle

menpo.io add pickle support, move to pathlib