Fix factor graph for models with a minus
Fix junction trees in D3
Added logI
ContinuousVar
(Discrete) Gibbs Sampling
Refactoring of macros to support ContinuousVar with ContinuousAtomicStructure. Conditioner now runs before factor graph generation, and *modifies* the corresponding metastructure.
Merge branch 'dev' of http://github.com/wolfe-pack/wolfe into dev