trying install matrix on travis
starting on max-product. first, testing if tree or not.

simplify is_tree procedure, test using mst.

slight refactoring (make n_vertices optional in is_tree, introduce edges_to_graph, start on message passing

tree max-product is working (omg?!)

misc fix in finding edge

test with non-repeating pairwise potentials

added tree test, not working :-/ small fixes

finally working on trees.... stupid me...

iterative max-product works

slight refactoring, include max-product in inference dispatch

add damping, stopping tolerance to max-product

example plotting potts model on grid, showing off different infernce algorithms

FIX: add relaxed keyword to inference_max_product.

upgrade tests for new version.
rename mp to max_product, add to inference method list
add lars' viterbi