add rudimentary support for uEye cameras

uEye are cameras from IDS, c.f. https://en.ids-imaging.com/
Supports driver version 4.94 and up currently, since the event system was overhauled there.
Supports setting/getting the properties: fps,width,height

modules/videoio/include/opencv2/videoio.hpp

@@ -120,6 +120,7 @@ enum VideoCaptureAPIs {
        CAP_OPENCV_MJPEG = 2200,         //!< Built-in OpenCV MotionJPEG codec
        CAP_INTEL_MFX    = 2300,         //!< Intel MediaSDK
        CAP_XINE         = 2400,         //!< XINE engine (Linux)
+       CAP_UEYE         = 2500,         //!< uEye Camera API
      };
 
 /** @brief %VideoCapture generic properties identifier.