Improve timer callback creation comment.

src/server.c

@@ -1959,8 +1959,9 @@ void initServer(void) {
     server.repl_good_slaves_count = 0;
     updateCachedTime();
 
-    /* Create out timers, that's our main way to process background
-     * operations. */
+    /* Create the timer callback, this is our way to process many background
+     * operations incrementally, like clients timeout, eviction of unaccessed
+     * expired keys and so forth. */
     if (aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL) == AE_ERR) {
         serverPanic("Can't create event loop timers.");
         exit(1);