Initial cuda-convnet2 commit.
Fixed paths in build files so things actually build (I hope).
10% faster first-layer conv fwd pass with 64N filters. Slightly faster single-GPU training due to removed extraneous sync points.
Merge branch 'master' of https://code.google.com/p/cuda-convnet2
15% faster conv fwd pass for 48N filters.
merging latest changes from alex's branch