BMO_ITER macros to make defining iterator loops easier. Moved some files around. And also made the editmesh conversion functions tesselate ngons to triangle fans, since it's more stable for conversion, and editmeshes are never displayed to the user anyway. And ported akey to bmesh. Next up I plan on adding face iterators to DerivedMesh, since that's the last major chunk of major refactoring left, I think, except perhaps the uv editor (at the moment it's probably close to working, but it's still converting to editmeshes for everything, which is very bad).