UD into main

[fginter]

I think we should make UD the default output and we should move from Alpha to Main. The parser was used to parse 5B tokens by now, it's no longer alpha grade. :)

[spyysalo]

+1

[jmnybl]

Note to myself: Main branch should be updated to contain UDv2.0 (merge branch ud_v2 and update model files).