Added expires directive and map to nginx, allowing browser to cache SOGO JS,CSS,WOFF files.

data/conf/nginx/site.conf

@@ -161,6 +161,7 @@ server {
     proxy_cache_valid 200 1d;
     proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
     #alias /usr/lib/GNUstep/SOGo/WebServerResources/;
+    expires $expires;
     allow all;
   }
 
@@ -171,6 +172,7 @@ server {
     proxy_cache_valid 200 1d;
     proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
     #alias /usr/lib/GNUstep/SOGo/WebServerResources/;
+    expires $expires;
     allow all;
   }
 
@@ -344,6 +346,7 @@ server {
     proxy_cache_valid 200 1d;
     proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
     #alias /usr/lib/GNUstep/SOGo/WebServerResources/;
+    expires $expires;
     allow all;
   }
 
@@ -354,6 +357,7 @@ server {
     proxy_cache_valid 200 1d;
     proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504;
     #alias /usr/lib/GNUstep/SOGo/WebServerResources/;
+    expires $expires;
     allow all;
   }