tests/test-1102

localrepo/branchcache: kill unused localrepo.branchcache

The UTF-8 version of the branchcache is the master, always up-to-date, we can
rename it to localrepo._branchcache.

#!/bin/sh

rm -rf a
hg init a
cd a
echo a > a
hg ci -Am0
hg tag t1 # 1
hg tag --remove t1 # 2

hg co 1
hg tag -r0 t1
hg tags