[html5/audio] Add hackViaWs to SIP.js and make it configurable in settings.yml, 1002 workaround

This adds the possibility to configure the SIP Via header to plain WS to allow reverse proxying from WSS to WS, internally, to work around a bug in freeswitch where the WSS stack would get deadlocked due to a still unidentified bug in there that has to do with SSL termination