Disable vJUD search in the default config and when not specified

ejabberd.yml.example

@@ -658,7 +658,8 @@ modules:
   mod_shared_roster: {}
   mod_stats: {}
   mod_time: {}
-  mod_vcard: {}
+  mod_vcard:
+    search: false
   mod_version: {}
 
 ##

src/mod_vcard.erl

@@ -94,7 +94,7 @@ start(Host, Opts) ->
 				  <<"vjud.@HOST@">>),
     Search = gen_mod:get_opt(search, Opts,
                              fun(B) when is_boolean(B) -> B end,
-                             true),
+                             false),
     register(gen_mod:get_module_proc(Host, ?PROCNAME),
 	     spawn(?MODULE, init, [MyHost, Host, Search])).