Add to example config file access_from comment

src/ejabberd.cfg.example

@@ -545,9 +545,17 @@
 		  %%
 		  %%{registration_watchers, ["admin1@example.org"]},
 
+		  %%
+		  %% Only clients in the server machine can register accounts
+		  %%
 		  {ip_access, [{allow, "127.0.0.0/8"},
 			       {deny, "0.0.0.0/0"}]},
 
+		  %%
+		  %% Local c2s or remote s2s users cannot register accounts
+		  %%
+		  %%{access_from, deny},
+
 		  {access, register}
 		 ]},
   %%{mod_register_web, [