#49 3.1.8 build errors with Visual Studio 2017 on Windows 10 x64

[divjak]

Hello!

First, let me thank you for creating and maintaining this library. I don't have much experience with it yet, but I'm planing to use it for marker detection for AR application on Hololens.

I just tried building the 3.1.8 version of the library on Windows 10 x64 with VisualStudio 2017 and OpenCV 4.1.2 and found some problems. Fortunately, they were easy to fix:

1. Undefined "u_int32_t" in files fractalposetracker.h and fractalposetracker.cpp, in method fractal_solve_ransac(). I changed it to "uint32_t".

2. Error calling the function "clock_gettime(CLOCK_MONOTONIC, &ts);" in the same fractal_solve_ransac() method. This function is not available under Windows. Since it doesn't seem very important (I don't plan to use the new fractal features), I simply commented it out.

3. Linker can't find the calls to "imshow" and "waitKey" in the FractalPoseTracker::drawKeyPoints() method. Since this seems only intended for debugging, I commented it out.

With those fixes, everything builds. However, the resultsing DLL file is called "aruco317.dll", it should probably have the new version number.

I hope this helps.

Best regards!