Support window build

[baothientran]

Fixes #17

• Downgrade GDAL to 2.4.1 to be compatible with GDAL in vcpkg.
• Change Math.h file to MathUtility.h since window mistakes the file with the standard header #include<math.h>
• Explicitly convert std::filesystem::path to std::string since on Window, std::filesystem::path seems to implicitly convert to std::wstring instead of std::string like gcc
• Remove OSG::JPEG plugin since we never use it
• Update instruction to compile on Window in the README file

[lilleyse]

@baothientran the code and README updates look good at a quick glance.

One thing - there are some files with a bunch of whitespace changes in the diff, looks like spaces were converted to tabs accidentally. Once that's fixed @likangning93 can do a final review and merge.

[baothientran]

@likangning93 @lilleyse I update the whitespace format in the new commit. It is ready for another review

[lilleyse]

Offline we talked about using conan which may fix the the GDAL issues