Improved README example ('views' param in UA.call).
Improved README example ('views' param in UA.call).

josephfrazier/SIP.js,onsip/SIP.js,DrumTechnologiesLtd/JsSIP,markandrus/SIP.js,tqcenglish/JsSIP,vconsult/JsSIP,Escaux/SIP.js,Voiceworks/SIP.js,onsip/SIP.js,CodeYellowBV/JsSIP,voxbone/JsSIP,dpocock/JsSIP,rusekr/JsSIP,joseph-onsip/SIP.js,ronlobo/SIP.js,AaronZhangL/JsSIP