Adds tagset for Portuguese using Palavras tagger
Adds tagset for punctuation
Fix unicode bug when sending traceback email
Merge branch 'feature/pt-palavras' into develop

Conflicts:
	pypln/web/apps/core/visualizations.py
Removes 'tagset' from required tags in POS visualization

The code already treats the case of the tagset not being in the database.
If we leave it in the requirements, a request in the url will be treated as 404
because the requirements won't be fufilled.