Remove unused $Id$ Git ident attribute

$Id$ keywords were used in Subversion where they were replaced with last
revision number, author, and time. In Git this functionality is
different and each file would need to be defined manually in the
.gitattributes file to be replaceable. This patch simplifies this with
reemoval of the Git ident attribute.

config.w32

@@ -1,4 +1,3 @@
-// $Id$
 // vim:ft=javascript
 
 ARG_WITH("xlswriter", "xlswriter support", "no");