Add docs on how to use mobile camera but launch front/back camera, restrict switching of the camera modes etc

[prasanth-reddy-wavemaker-com]

https://docs.wavemaker.com/learn/app-development/widgets/mobile-widgets/camera#docsNav

Needs to include details on how to launch the front facing camera or back facing camera. Once the cell phone camera is launched is there a way to not show the control to switch the camera mode?