FIX: Do not index when no translation or too big unit text.
API: Update Mustache to newer version (8.2)

Needed to not default to parent's attribute when current object's attribute
exists but is empty (=> `doc.translations[t].work_creator` vs `doc.work_creator`)
FIX: Do not prefill translation's information with original ones.

Conflicts:

	couchdb/_attachments/work.js
	couchdb/updates/work.js
	couchdb/views/concordance/map.js