Gut was freezing on some integration tests. It was also entering an
infinite loop after exiting (even after closing Godot and VSCode) which
caused a `godot.log` file in app_userdata to keep growing until my hard
drive was full.
Uses fork of node-pty native code for forking pseudoterminals.
Uses libuv pipe handle to communicate with the child process.
- Paves the way for cross-platform (Linux, macOS and Windows) support.
- Renames Pseudoterminal to PTY (which is much easier to type and spell :D).
- Better performance than the old Pseudoterminal node. Especially when
streaming large amounts of data such as running the `yes` command.
- Allows setting custom file, args, initial window size, cwd, env vars
(including important ones such as TERM and COLORTERM) and uid/gid
on Linux and macOS.
- Returns process exit code and terminating signal.
