For now, limited to the most repetitive rules that are also short and
simple, so that we can have a substantial conciseness win without
compromising rules readability.

Ran rulegen, no changes in the rewrite files.

Change-Id: I8447784895a218c5c1b4dfa1cdb355bd73dabfd1
Reviewed-on: https://go-review.googlesource.com/95955Reviewed-by: Giovanni Bajo <rasky@develer.com>