Coverage for remote follows (#2694)

Coverage for remote follows (#2694)

* Add coverage for create with empty acct value

* Add coverage for create with webfinger failure

* Add coverage for create with webfinger providing bad values

* Add coverage for create when webfinger is good

* Add coverage for session[:remote_follow] having data

* Simplify how remote follow pulls acct from session

* Remote follow behaves more like model

* Move the discovery portions of remote follow out of controller

* Check for suspended accounts