Patch: Unix Domain Socket Forwards for 4.4p1

[William Ahern]

I've updated the streamlocal patch for OpenSSH 4.4p1.

	http://www.25thandclement.com/~william/projects/streamlocal.html

This patch allows for local and remote forwards, to and from Unix domain
sockets. Simply specify the socket path, enclosed within squares braces
(i.e. -L[/tmp/.s.PGSQL.5432]:[/tmp/.s.PGSQL.5432]) as the origin and/or
destination of the -R and -L switches. This patch also includes additions to
the regression suite.

Because I haven't had the time to separate them out, this patch incorporates
two other features:

1) Explicit user/group restrictions on control sockets (instead of the fixed
"sameuser or root" policy).

2) Being able to specify an explicit protocol banner for sshd.