Add new options remove_new_unused_deps and remove_unused_kernel

In unattended_upgrades > 2.5 is possible to configure unattended
upgrades to remove unused kernel packages and remove new unused
dependencies. This commit exposes this functionality to the puppet
module without changing the default.

If the new values are not set, nothing changes.

Based of code from Stephan Eicher <stephan.eicher@check24.de>