Cast to (int) to avoid warnings

Add test for different points number case in fisheye calibration function

- Still need to change SSE_2

I have seen that you can input a Mat_<float> on StereoBM, but the value seems the same as CV_16S.
I changed it so, only if you input a Mat_<float> it makes use of a previously truncated 4 bits, giving more resolution to Disparity Matrix. (The algorithm stays the same, it's not more precise).
If any other input Mat is given, it changes nothing.

Modified and improved the method for chessboard detection. It is now faster and detects chessboards under difficult lighting condition as well as when the chessboard has strong out of plane rotations

  * resolve #5183

All of these: (performance) Prefer prefix ++/-- operators for non-primitive types.
[modules/calib3d/src/fundam.cpp:1049] -> [modules/calib3d/src/fundam.cpp:1049]: (style) Same expression on both sides of '&&'.

Fix for inconsistent asserts in cv::fisheye::initUndistortRectifyMap() which prevents from passing empty matrices in debug build (which is allowed according to the code bellow the asserts and the docs).

The FOV depends on the principal point location. Use formula of
viz::Camera.

Added a writeFormat() method to Algorithm which must be called by the
write() method of derived classes.

cosmetic changes to fix this warning.
real bugs not found

Fixed getSubset method to support Nx3 1-channel matrices as input (3xN 1-channel matrices doesn't supported at all).

Added test for checking that solvePnPRansac accepts vector<Point3f> and Nx3 1-channel or 1xN/Nx1 3-channel matrices as input.

With a test image set of 2800x1400 bytes on a Intel Core i7 5960X this improves runtime of MODE_HH with about 10%. (this particular replaced code segment is approx 3 times faster than the non-SSE2 variant). I was able to reduce runtime by 130 ms by this simple fix.

The second part of the SSE2 optimized part could probably be optimized further by using shift SSE2 operations, but I imagine this would improve performance 10-20 ms at best.

Extension of the camera distortion model for tilted image sensors (Scheimpflug condition) including test

if they are not we also do not need to allocate a local copy of the rvec
and tvec

also replace C defines with C++ enums