Fix/document Windows compatibility issues

[dustin-jw]

Folks developing on Windows have run into some issues that we should try to fix or at least document. Known issues:

• npm scripts with `INLINE_ENV_VAR=something run command" will fail unless the user has bash configured to run npm scripts
• Slow file IO makes composer installs/updates incredibly slow (recommend not mapping the root directory in run.sh)
• Volume mappings in docker run command need to be escaped to avoid absolute path errors
• Git'sautocrlf setting causes line endings that make the lint:php script fail (should disable the "Generic.Files.LineEndings.InvalidEOLChar" rule)
• Lack of PHP support on Windows renders the phpcs and twigcs VS Code extensions useless (can possibly work around with the Dev Containers extension)