virginia (UVA): name parts order fix
Minimize use of regex in cleanup_language

- Make two dictionaries in is639_3.py, one with single-word
  reference names and one with multi-word reference names
- Update the cleanup_language module to split the language value by
  whitespace and check if in single-word dict.
- Use regex matching only with multi-word dict
- If languages is empty, delete the prop
virginia (UVA) creator order fix + test
Merge branch 'develop' into virginia