Should address edge cases and close#224 -- subject to field testing.
Does require the NGINX deployments use the following:
proxy_pass <http://documize-url:5001>;
proxy_set_header Host $http_host;
proxy_set_header X-Forwarded-For $remote_addr;
1. handle long username overflow on space permissions screen
2. only show document history to editors
3. removed redundant document editing permission check
4. Ensure subdomain is detected when accepting space invitation