* Add a way for users to specify custom upstream directives via .upstream.conf file;
* MiaB-managed applications and user applications will now use different sockets;
* Split the nginx templates again so we have just the part needed to make a domain do a redirect separate from the rest.
* Add server blocks to the nginx config for these domains.
* List these domains in the SSL certificate install admin panel.
* Generate default 'www' records just for domains we provide default redirects for.
Fixes#321.
