Trading page + navbar refactor

Add the empty trading page.
Refactor the navbar into a template.
Change jshint settings to enforce 2 space tabs.
Delint files that were touched.

Fixes #763.

~~TODO: Before merging, ensure that clicking an invite link then logging in still works. I'm 100% sure that the code I removed was unreachable, but I want to make sure that the functionality was implemented elsewhere.~~