V1 refactor tracking PR

This is a tracking PR (not ready for merge). This PR is a full rewrite of the frontend code to no longer use Mercury and to use the pluggable 3-tier (ssb, apis, gui) architecture.

Still todo:

 - [x] view msg raw toggle
 - [x] text posts
 - [x] action posts
 - [x] replies
 - [x] reactions
 - [x] threaded feed page
 - [x] inbox page
 - [x] network page
 - [x] profile page
 - [x] message thread page
 - [x] help page
 - [x] setup page
 - [x] 404 page
 - [x] follow btn
 - [x] view my id btn
 - [x] assign nickname btn
 - [x] suggest box
 - [x] sync btn
 - [x] unread messages count (inbox)
 - [x] connection drop alert