Login Time Issue

Fixes #940 and fixes #863

This is built on top of 2factor auth pr so merge that one in first. 

This tries to get the current login from the auth server instead of relying on the auth cookie the dashboard sets. This also properly fixes the dashboard redirect bug-- (the problem that I discovered in #913). Instead of loading any extensions on login, it waits for an event called `signInTransition` to fire