Address OpenCV fisheye symbol collision

[ds58]

This PR should address #1185

OpenCV has cv:::initUndistortRectifyMap and cv::fisheye::initUndistortRectifyMap in the calib3d module. The Java for the fisheye version wasn't getting generated because of the symbol collision. I added a javaNames for the fisheye version so it maps to fisheyeInitUndistortRectifyMap

[saudet]

Looks good, thanks! While we're it, let's also prefix with "fisheye" all functions from thecv::fisheye namespace?
If I'm not overlooking anything, the complete list is:
cv::fisheye::projectPoints
cv::fisheye::distortPoints
cv::fisheye::undistortPoints
cv::fisheye::initUndistortRectifyMap
cv::fisheye::undistortImage
cv::fisheye::estimateNewCameraMatrixForUndistortRectify
cv::fisheye::calibrate
cv::fisheye::stereoRectify
cv::fisheye::stereoCalibrate

[ds58]

While we're it, let's also prefix with "fisheye" all functions from thecv::fisheye namespace?

Yes, I think that's a good idea. I've done that.