stgit: premerge hooks and preventing errors

What's the status of using premerge hooks to stop git merge/pull from
messing up stgit? I just messed up another stgit tree by doing git
pull on it. I've learned how to fix this by rolling back the head, but
this mistake is way too easy to make.

Even though I'm aware that this mistake is possible and I'm still
making it. When you have a mix of git and stgit trees it is very easy
to forget which one you are on.

-- 
Jon Smirl
jonsmirl@gmail.com