Initial LDA/CVB/0 commit

Added a vocab method to all models as LDA is the first model not to
explicitly store a vocab.

Moved the configuration of PyxImport into the module init files.
Better commenting of vocab function
Fix bugs in LDA test, update to use new API
Add a lot of debugging to lda/Cython to track down some NaNs
Vocab function was buggy. So was log likelihood.
Accidentally committed generates so.reload1 file.
Debug in LDA/CVB didn't properly format args in print