CHANGES:
- Separated 3d tensors from 2d tensors in initialization and tree representation computation.
- Store random matrices that are used for tree computation as part of the model.
- Fixed a bug in ExtractFeatureTypeValuePairs: previously, it was not handling word types that fall below the cutoff value.
- Fixed a bug in computing partial marginals and tree representations when i = j: previously, it was giving 0 representation for p(a -> x|a) = 0. Now it doesn't assign any representation when that happens.
- Improved message printing.