Added flip option in camera.cpp

[Skammi]

@OTL Added n option to flip the image at source to accommodate for cameras that have to be mounted up-side down. Without the option to flip the Image in the camera. Use the cv:: flip() function and 2 parameters. One to indicated to flip and one the flip code for the cv::flip() function. Default is not to flip. When flip is enabled the default flip code is to flip over both axes.

Thanks, Jacob