MINIFICPP-464 Clarify GetUSBCamera docs regarding scheduling behavior and image quality selection
MINIFICPP-464 Clarify GetUSBCamera docs regarding scheduling behavior and image quality selection

This closes #309.

Signed-off-by: Marc Parisi <3cd89688bb0a35b1f4229ca5a98e5d7bf31861da@apache.org>

achristianson/nifi-minifi-cpp,achristianson/nifi-minifi-cpp,phrocker/nifi-minifi-cpp,apiri/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,kevdoran/nifi-minifi-cpp,apiri/nifi-minifi-cpp,apiri/nifi-minifi-cpp,kevdoran/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,jdye64/nifi-minifi-cpp,apiri/nifi-minifi-cpp,phrocker/nifi-minifi-cpp,kevdoran/nifi-minifi-cpp,jdye64/nifi-minifi-cpp,achristianson/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,jdye64/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,phrocker/nifi-minifi-cpp,jdye64/nifi-minifi-cpp,kevdoran/nifi-minifi-cpp,phrocker/nifi-minifi-cpp,achristianson/nifi-minifi-cpp,phrocker/nifi-minifi-cpp,apiri/nifi-minifi-cpp,kevdoran/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,jdye64/nifi-minifi-cpp