Add a dev env setup guide for Windows (MSYS2)

[rdw-software]

Same as #65

Windows Env Setup:

1. Download MSYS2
1. Get Windows Terminal from MS Store (or Cmder from GitHub)
1. Install zsh, zsh stuff if you want it prettier
1. install stuff via pacman (existing docs)
1. Stylua -> cargo -> 
	pacman -S mingw-w64-x86_64-rust
	cargo install stylua
	add bin to path (C:\Users\name\.cargo\bin

For the docs:

pacman -S mingw-w64-x86_64-nodejs

See https://packages.msys2.org/package/mingw-w64-x86_64-nodejs?repo=mingw64

(Just kidding, of course it doesn't work... Have to forward the path or start a separate MINGW shell, e.g. F:\MSYS2\msys2_shell.cmd -defterm -here -no-start -full-path -mingw64 -shell zsh)

Test via echo $PATH (should include /mingw64/bin and NOT the windows paths

For uws tests (autobahn): Docker etc

Add to bashrc or zshrc:

export PATH="$PATH:/c/Program Files/Docker/Docker/resources/bin"

(with the right path, obviously)

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Windows Terminal does not render Uncicode properly (e.g., for the PASS/FAIL icons used in the test suite)

Solution (Windows 10): Enable this setting under Region -> Administrative -> Change System Locale ...

"Beta: Use Unicode UTF-8 for worldwide language support" (checkbox)