Instead of adding a job to create the socket and call bind(), do it
straight from the serve() method, this allows the caller to set
umask(), permissions and so on.
Document this behavior in the class, since we can't extend the
method's documentation.
This introduces AF_UNIX server and dialer, these are not available on
Windows as in that platform we'll create a custom class for native
'local' communication.
In the future we can add a wrapper class Efl.Net.Local that will use
the class for each platform, but won't expose its details.
For instance, if we ever expose 'credentials' (which I didn't because
they are not portable), then it doesn't make sense to try to match
that on Windows. The 'Efl.Net.Local' would just stick to the basics:
Reader, Writer and Closer APIs.