Qt4: rework HTTP sout box

Qt4: rework HTTP sout box

The address field is removed, as it is quite useless. The default
unspecified value works just fine. In fact, it works better than
0.0.0.0 as it allows both IPv6 and IPv4 automatically.

A new path field is added for the local path, defaults to '/'
consistent with HTTP URI semantics ("http://www.example.com" really
means "http://www.example.com/").