pythonPackages.gcutil: Deprecate the package

The package doesn't exist anymore (even the deprecation notice is gone
[0]) and the build is currently broken:
Collecting google-apputils==0.4.1 (from gcutil==1.16.1)
  Could not find a version that satisfies the requirement
google-apputils==0.4.1 (from gcutil==1.16.1) (from versions: )
No matching distribution found for google-apputils==0.4.1 (from
gcutil==1.16.1)

[0]: https://download.huihoo.com/google/gdgdevkit/DVD1/developers.google.com/compute/docs/gcutil.1.html
> "Warning: gcutil is deprecated. We encourage you to transition to
> using gcloud compute ."