Remove unused Git attributes ident

The `$Id$` keywords were used in CVS and Subversion where they can be
substituted with filename, last revision number change, last changed
date, and last user who changed it.

In Git this functionality is different and can be done with Git
attribute ident. These need to be defined manually for each file in the
`.gitattributes` file and are afterwards replaced with 40-character
hexadecimal blob object name which is based only on the particular file
contents.

This patch simplifies handling of `$Id$` keywords by removing them since
they are not used anymore.

cron/README

@@ -1,5 +1,3 @@
-// $Id$
-
 Cronjob Wrapper for Docweb
 
 This directory tree allows pseudo-crontab manipulation whenever CVS updates,

include/lib_proj_lang.inc.php

@@ -19,7 +19,6 @@ vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4:
 |                   Gabor Hojtsy <goba@php.net>                        |
 |                   Sean Coates <sean@php.net>                         |
 +----------------------------------------------------------------------+
-$Id$
 */
 
 // split from lib_general.inc.php

scripts/gen_doc_activity_email.php

@@ -15,7 +15,6 @@
 +----------------------------------------------------------------------+
 | Author:        Philip Olson <philip@php.net>                         |
 +----------------------------------------------------------------------+
-$Id$
 
 Notes: 
 	- This emails the documentation list each # days (7, via cron) with 

www/redirect.php

@@ -15,7 +15,6 @@
 +----------------------------------------------------------------------+
 | Authors:          Sean Coates <sean@php.net>                         |
 +----------------------------------------------------------------------+
-$Id$
 */
 
 require_once('../build-ops.php');