cythonized watershed_util
cython for distutils
watershed pyx and py now match
Merge branch 'master' of github.com:jwayne/iw-seung

Conflicts:
	.gitignore
	oversegmenters/watershed_it.py
	oversegmenters/watershed_mod.py
	oversegmenters/watershed_util.pyx
	setup.py
	structs/formats.py