Override the default plural forms for a language on the server.
Allow Zanata admin to override default plural forms in pluralforms.properties.
- Changes in UI for admin to input new plural forms
- Changes in HLocale table for new column,
- pluralforms in HDocument should still has the highest priority, follow by data from HLocale, and finally pluralforms.properties.
Verified merge (master) at 062565c69a67bdfba201613c3a47a41a012a0edf