config: rename `revlog` section into `storage`
The idea was suggested by Gregory Szorc on IRC. It is more generic and seems
better. It is probably best to rename the section before it ever makes into an
official (non-rc) release.
The only config option currently in this section have been prefixed with
`revlog` to clarify it applies to `revlog` related storage.
#require docutils gettext
$ $TESTDIR/check-gendoc ru
checking for parse errors