manual username & password input

fixes #2295
when using browser/plugin auto-complete from what I understand certain browser events
are not emmited and thus angular never picks up the new values.

This patch adds a fallback using jQuery to set the username & password if the angular
properties are not set.

see: https://github.com/angular/angular.js/issues/1460
Add popover quest description to quests in the Market and add buyQuest modal to show text and rewards before purchasing the quest
Close quest modal after quest purchase
Fix version conflict
Don't show information if the quest is locked
Make locked quests purchasable
Remove level lock to purchase
Replace string for env.t
Split main.json
Fix version conflict
Fix version conflict
Market "Sell..." button: add spaces, remove bracket

Fix some text appearance issues:

- Use item.text instead of item.key so that users see "Tiger Cub" rather than "TigerCub".

- Remove unwanted ) from end of gold value so that users see "3 Gold" instead of "3) Gold". Bracket had been left over from the end of the old env.t(...) function call - see https://github.com/HabitRPG/habitrpg/commit/4f07ab39b0868764c665bbf914474745e11ecc32

- Add spaces between words so that users see "Sell Fox for 3 Gold" instead of "SellFoxfor3Gold". There are other shorter/neater ways to insert those spaces, but making them really obvious with nbsp is probably the best way to ensure they don't get accidentally removed again.
Replace hard-coded strings for env.t on drops.jade file
chore(license): remove conflicting text (fixes #2596), and simply reference the GPLv3 file by URL. Assets & content designed by BQ are CC-BY-SA, for HabitRPG are CC-BY-NC-SA
feat(premium): backport client-side premium code to public repo, it's
client-side anyway (@colegleason @paglias)
Remove duplicated 'none' and minor adjusts
feat(homepage): start cleaning up homepage, add navbar for play button & upcoming links
feat(administrators): start adding features page for admin accounts
feat(attributes): Add backfill button in flat and classbased allocation modes

Partial implementation of a "distribute points now" button for backfilling accrued Attribute points. Works with flat and classbased allocation so far; taskbased will require much fancier handling.
feat(premium): updates to group plans info page