Modified sources in order to compile with MSVC compilers:

[emruiz81]

• Declaring arrays in the stack with variable size is not allowed by C standard, although some compilers like GCC allow it, MSVC doesn't. So I've changed all the places where this happens and allocate a HEAP array instead, but only for MSVC. Non MSVC compilers keep working as before
• Make a DLL interface macro so we can import the library in a standard way
• Added #define NOMINMAX to avoid conflicts with min and max macros in Windows.h
• Disable OMP reduction for now in MSVC, it doesn't work

NOTE: In order to compile this with MSVC, you need to create the project files with CMAKE, and set the openmp flags to openmp:experimental

[lock042]

@heckflosse , @CarVac , @emruiz81 : This PR breaks our msys2 compilation as you can see here: https://gitlab.com/free-astro/siril/-/jobs/4419131045

[emruiz81]

I'm sorry for that, I'll take a look today and try to fix it asap

[emruiz81]

@lock042 I've created a new PR #75 to address this issue because this one is closed. I've tested it with your siril build environment and is working OK.