Lots of localization updates (esp. to support Farsi):

- New UI components CSS marked up for flipping.
- Fixed visual bugs related to RTL display.
- Marked strings for translation in both js and template files.
- Lesson tasks now pull data from set language of user.
- Changes to database, to demonstrate how content should be added to grammar topics in the UI.
- Ran commands to collect localization files for FA, DE, IT, HR.