Build docker image in gitlab, add docs for turn key docker setup

docker/conf/nginx.conf

@@ -0,0 +1,20 @@
+server {
+    listen 80;
+    location = /favicon.ico { access_log off; log_not_found off; }
+    location /static {
+        alias /var/www/myauth/static;
+        autoindex off;
+    }
+
+    location /robots.txt {
+        alias /var/www/myauth/static/robots.txt;
+    }
+
+    location / {
+        proxy_pass http://allianceauth:8000;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header Host $host;
+        proxy_set_header  X-Real-IP   $remote_addr;
+        proxy_redirect off;
+    }
+}