www/nginx: some bugfixes; add a rule for the upcoming naxsi release; add restart action to acme (#742)

* www/nginx: some bugfixes; add a rule for the upcoming naxsi release
* www/nginx: theme the two other error pages like the waf error page
* security/acme-client: allow to restart nginx (if installed)
* add .idea to gitignore
* bump versions and upcase nginx