adds basic functionality graphs and trees
adds MST
adds graphs tests
adds __str__
adds PointTree
Change to British spelling

Change center to centre
Change color to colour
Fix some docstrings

Major changes happen in PCA, keyword arg center becomes centre
Move extract_pathes_local to image

Changes to a more efficient Cython version as well
adds relative locations
Merge pull request #479 from patricksnape/extract_patches_on_image

Extract patches on image
Merge pull request #480 from nontas/graphs

Graphs functionality
Remove all traces of Mesh IO

Moving it all into Menpo3d
Remove mesh export

Also, stop making temporary files for exporting tests
Remove 3d visualisation from menpo

It will try to import it and raise an exception if
menpo3d isn't installed.
Remove 3D dependencies
Didn't create the exception properly

Just make the message and raise an ImportError
AAM doesn't have an interpolator
Refactor the widget strings so they are cleaner

Just create a couple of simple functions that take raw strings
and spit out the latex code for the widgets. Looks a bit cleaner
in code and should make it easier to make more widgets.
Fix bug in serialized and fitting results widgets

Both bugs caused by me
Merge pull request #481 from patricksnape/remove_3d

Remove 3D
OS X isn't allowed to fail any more