Merge branch 'refs/heads/t/abtract_sockets'

Was cooking for almost one month and seems to work fine.

	manual: Move /var/paraslash instructions to Troubleshooting.
	Abstract sockets for server and audiod.
	create_local_socket(): Avoid code duplication.
	net.c: Combine remote_name() and __get_sock_name().
	Remove socket address parameter of create_local_socket().