Fix Issue 75:  [jain-sip.js] bug in sdp package: call getMedia() on MediaField, should call getType() in SessionDescription copy operator
Fix Issue 76: [jain-sip.js] bug in sdp package: still attributeFields member existing, should be renamed attributeFieldsArray in MediaSdesciption.js:
[jain-sip.js] Library release with Fix  75, 76
Implement Enhancement 74: [WebRtcComm.js] Provide default audio/video codecs to used (overload RTCPeerConnection SDP offer) in the call configuration
[WebRtcComm.js] Library release with Enhancement 74
[WebRtcCommTestWebApp] Implement Enhancement 74: Provide default audio/video codecs to used (overload RTCPeerConnection SDP offer) in the call configuration