core: move comments with description of C file to top of files

src/plugins/rmodifier/rmodifier.c

@@ -1,4 +1,6 @@
 /*
+ * rmodifier.c - alter modifier strings with regular expressions
+ *
  * Copyright (C) 2010-2012 Sebastien Helleu <flashcode@flashtux.org>
  *
  * This file is part of WeeChat, the extensible chat client.
@@ -17,11 +19,6 @@
  * along with WeeChat.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-/*
- * rmodifier.c: alter modifier strings with regular expressions
- *              (useful for hiding passwords in input or command history)
- */
-
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>