Add a scheme for handling remote locking
This adds an object that remembers to unlock the remote repo on
destruction and lock/unlock functions for the ssh protocol. The remote
repository should also unlock itself when the connection goes down.
+ hg init
+ echo '[hooks]'
+ echo 'precommit = echo precommit hook'
+ echo 'commit = echo commit hook: $NODE'
+ echo a
+ hg add a
+ hg commit -t test -u test -d '0 0'
precommit hook
commit hook: acb14030fe0a21b60322c440ad2d20cf7685a376