Batch scripts in general will not function without carriage return line
endings on Windows. We rely on these scripts to support cmd, so we
should not allow these scripts to be converted to lf.
Note: Windows 11 supports lf line endings due to the use of Windows
Terminal. Once support for Windows 10 is dropped, this change can be
reverted.
This PR enables the successful execution of the spack binary cache
tutorial on Windows. It assumes gnupg and file are available (they
can be installed with choco).
* Fix handling of args with quotes in spack.bat
* `file` utility can be installed on Windows (e.g. with choco): update
error message accordingly
