tests/test-issue1175

localrepo: rename in-memory tag cache instance attributes (issue548).

- self.tagscache to self._tags
- self._tagstypecache to self._tagtypes
- this is for consistency, readability, privacy, and to subtly hint
  that "caching" is something else

#!/bin/sh
rm -rf a
hg init a
cd a
touch a
hg ci -Am0
hg mv a a1
hg ci -m1
hg co 0
hg mv a a2
hg up
hg ci -m2

touch a
hg ci -Am3
hg mv a b
hg ci -Am4 a
hg ci --debug --traceback -Am5 b
hg verify
hg export --git tip