Rename MODULE_INFO to MXS_MODULE

The MODULE_INFO is now the main object which is used by modules to convey
information to the MaxScale core. The MXS_MODULE name is more apt as it
now contains the actual module definition.

The old MODULES structure was moved into load_utils.c as an internal
implementation and was renamed so that it is not confused with the new
MODULE structure.

server/modules/authenticator/CDCPlainAuth/cdc_plain_auth.c

@@ -143,7 +143,7 @@ static bool cdc_add_new_user(const MODULECMD_ARG *args)
  *
  * @return The module object
  */
-MODULE_INFO* MXS_CREATE_MODULE()
+MXS_MODULE* MXS_CREATE_MODULE()
 {
     static modulecmd_arg_type_t args[] =
     {
@@ -166,10 +166,10 @@ MODULE_INFO* MXS_CREATE_MODULE()
         cdc_replace_users               /* Load CDC users */
     };
 
-    static MODULE_INFO info =
+    static MXS_MODULE info =
     {
-        MODULE_API_AUTHENTICATOR,
-        MODULE_GA,
+        MXS_MODULE_API_AUTHENTICATOR,
+        MXS_MODULE_GA,
         GWAUTHENTICATOR_VERSION,
         "The CDC client to MaxScale authenticator implementation",
         "V1.1.0",