Doc cleanup

* Fixed all the errors reported when building the docs with sphinx
* Pulled ImageCms out into it's own page (also asserted (c) for my lcms2 changes as of 2013-10)
* Couple of makefile changes that make it easier to build quickly.

Still todo, but probably in different PR:
* Convert OleFileIO to use the param style that we use elsewhere. This may make merges harder, but the docs will be better. 
* Pull OleFileIO and ImageMorph and anything else that has significant docs out of the catchall PIL.rst file and into their own pages.