windows support

[matu3ba]

Not sure what is unclear to you from child_process.zig, so briefly starting the talk here.

1. Windows only has named pipes, anonymous ones are silently also using named ones.
2. Windows has flags for a pile of things, but using the CreateProcess ones for standard streams should be sufficient. Make sure you have inheritance enabled and you're using one of the (I think 4 or 5) working ways if necessary.
3. Subsituting stdout works via https://stackoverflow.com/questions/54094127/redirecting-stdout-in-win32-does-not-redirect-stdout
4. All the other Windows stuff is just as complex. You probably dont want to do the complete PATH dance, but that is up to you.

[liyu1981]

thanks @matu3ba, I will spend some time to research this ;O

[jcs090218]

Second this. Definitely need the windows support!