obshistory: restructure templates a bit, drop default verb ("pruned")
We always have a verb provided to the templates now, this should be fine.
Enable obsolescence to avoid the warning issue when obsmarkers are found
$ cat << EOF >> $HGRCPATH
> [experimental]
> evolution = all
> EOF
$ $TESTDIR/../contrib/check-compat-strings.sh "$TESTDIR/../hgext3rd/" "$RUNTESTDIR/.."