SSH transport should support port number

[Tenzer]

Here's a pretty trivial patch for adding the port number to the new SSH transport feature. The patch should apply cleanly against both 2.0 alpha2 and trunk.

This allows you to specify the port number for nodes connected with SSH in the format:

address ssh://munin-node-user@host.example.com:2222/path/to/munin-async-client --spoolfetch

When no port number is specified, it will default to port 22, due to the URI module setting that as default when no port number is mentioned in the URI.

Note that with this patch, it is no possible to specify the port number of remote hosts in ssh_config(5), since the '-p' parameter is used to ssh(1), which overrules any settings specified in ssh_config(5).
Since the URI module defaults to port 22, I couldn't find a way to work around this, since I can't know if the port number is specified through munin.conf, or it's just the default.

[snide]

Applied on trunk in r4153.

Thx.