VS 2019 compatibility

[nilsnolde]

fixes #448

Note, I only tested building the static vroom library and the vroom main executable with these changes. I confirmed with example_2 that it works in an offline scenario. I didn't have the time (yet) to try anything else.

Also, no idea how to manually build this with VS toolchain (and zero interest wanting to know;)), I actually used CMake. Which I'll contribute separately (gotta give that a test on linux first).

In any case, the changes are a few missing includes and some ifdefs, nothing intrusive. Oh, and getopt is not available for MSVC, so I needed to borrow one from mingw64.

Tasks

• Update CHANGELOG.md (remove if irrelevant)
• review

[nilsnolde]

And don't sweat it if you don't want to include VS support.. This is really easy to maintain and patch in a fork. Same with CMake support..

[jcoupey]

Thanks for submitting a PR! I have no real interest for win builds myself and I guess few users have based on the low number of complaints we've had so far. ;-)

On the other hand, if this only means adjusting includes and some compilation-related stuff, I'm fine with including the changes.

What bothers me most is the need to have an unrelated getopt implementation in the codebase. Could we at least have it live in the include directory alongside the rapidjson dependency?

[nilsnolde]

have it live in the include directory

Sure, better idea anyways.

[nilsnolde]

Also tested ORS on windows quickly btw to make sure the HTTP stuff is working as well.

[nilsnolde]

Let me do the following once I'm back on win:

• adapt changelog
• fix the include for the new location of getopo_win.h
• experiment with some directives to not include Win headers defining some crap macros

[nilsnolde]

alright, impact on the codebase minimized:) good to go from my side

For future reference: this won't compile with MSVC unless you include the NOGDI preprocessor directive, which makes sure WinGDI.h is not pulled in causing all sorts of trouble. For good measure, include WIN32_LEAN_AND_MEAN, bringing down the compile time by a minute or two..

[jcoupey]

Except for the changelog conflict, this is good to merge.