pv: new variable $su to return source address in uri format

- $su is expanded "sip:$si:$sp;transport=$pr"
- example: "sip:127.0.0.1:5060;transport=udp"
presence: reduce verbosity for log message printed when sending notify

- info changed with dbg
- patch by Luis Azedo <luis.azedo@factorlusitano.com>
dispatcher: reset whitespaces to tabs for identation