Blender Git Loki

===Tools===
Adding back some code to booleans that got lost in the Orange merge.

I've also added back the code which checked that meshes were solid
("manifolds") but have the actual check in
intern/boolop/intern/BOP_Interface.cpp, since from my testing it was
not causing crashes or hangs. It *can* give odd results depending on
what you're trying to intersect, but seems useful. Additionally, since
existing bugs in the current code can create non-solid/non-manifold
meshes, seems hypocritical to create a mesh that can't later be used in
another boolean operation.