tags: return tags in sorted order
This makes log and summary have less arbitrary tag ordering and also
groups similar tags together, such as the mq tags.
#!/bin/sh
# test update logic when there are renames
# update with local changes across a file rename
hg init a
cd a
echo a > a
hg add a
hg ci -m a
hg mv a b
hg ci -m rename
echo b > b
hg ci -m change
hg up -q 0
echo c > a
hg up
cd ..