[MERGE][#109143] Support bzr+ssh://host/~/path

[Stefan Monnier]

> So suppose we later get a bug asking why ~user doesn't work in
> bzr-over-tcp.  We'd then need to change the server to do expanduser
> when it maps the paths its given into local urls.  That seems
> redundant with doing it at the SSH level.

IIUC, the issue of ~ is separate from the issue of ~user.


        Stefan