Fix email notifications for @-replies that come via OStatus.

* Moved notification sending from Notice::saveReplies to distrib queue handler, so it'll pull from the reply set we've saved regardless of how we got it.
* Set up gettext infrastructure for command-line scripts; gets localization mail notifications etc working from background queues.
* Adjusted locale switching: common_switch_locale() works at runtime for bg scripts, forces a message catalog update

scripts/commandline.inc

@@ -123,6 +123,10 @@ require_once INSTALLDIR . '/lib/common.php';
 
 set_error_handler('common_error_handler');
 
+// Set up the language infrastructure so we can localize anything that
+// needs to be sent out to users, such as mail notifications.
+common_init_language();
+
 function _make_matches($opt, $alt)
 {
     $matches = array();