====== muteCam() ======
wrtc.muteCam(true) stops use of local camera on //all// current calls. Transmitted media stream will transmit empty picture that -depending on implementation- either will show black image at receiving end or freeze last image transmitted.

wrtc.muteCam(false) will enable use of local camera again. Transmitted media stream will transmit current camera image again.

===== Arguments =====
wrtc.muteCam(stop)
  * stop - boolean, true to stop use of local camera, false to start using it again

===== Returns =====
Nothing.

===== Events =====
None.