and move to switch_utils. To allow use by other modules.

sofia-sip: extend timeout for session expires on short timeouts to be 90% of timeout instead of 1/3 to handle devices that do not refresh in time such as polycom (SFSIP-212)

mod_sofia: use rfc recommended default session timeout of 30 min according to RFC 4028 4.2 (MODSOFIA-76)

mod_spandsp: add start_tone_detect/stop_tone_detect app and api commands for tone and cadence detection (MODAPP-378)