video: renegotiate when switching input

daemon/src/call.h

daemon/src/client/callmanager.cpp

daemon/src/client/videomanager.cpp

daemon/src/dring/callmanager_interface.h

daemon/src/managerimpl.cpp

daemon/src/managerimpl.h

daemon/src/media/video/video_input.cpp

daemon/src/media/video/video_input.h

daemon/src/media/video/video_rtp_session.cpp

daemon/src/media/video/video_rtp_session.h

daemon/src/sip/sdp.cpp

daemon/src/sip/sdp.h

daemon/src/sip/sipcall.cpp

daemon/src/sip/sipcall.h

daemon/src/sip/sipvoiplink.cpp