Project initialize command.

This may be useful if you directly cloned a Platform.sh repository (and perhaps started work).

It is possible to run the command from inside the repository directory, but it leaves the shell in a weird state, at least when using ZSH (it reports the wrong cwd). I don't know of a way (from PHP) to `cd` on behalf of the user. So this warns you:
> Project initialized in directory: /absolute/path/to/projectRoot
> Type 'cd .' to refresh your shell