make tests on binary grid faster
move binary grid tests to learner tests
make latent subgradient test more robust and faster.
reorganize more tests, make them much faster
fix default inference for latent grid crf, more sane tests.
somewhat smaller test for latent node crf learning.
intermediate stuff
Add pascal image segmentation example
FIX setting n_edge_features in EdgeFeatureGraphCRF, make test use it.
DOC Clean up examples
speed up latent svm example
add unary inference to docs