Fix (#10440) by making all commands optional

Fix (#10440) by making all commands optional

This will work around the issue in http://projects.puppetlabs.com/issues/6907, as the agent run will no longer fail if one of the commands is not installed.

This gives you enough time to install the necessary packages through Puppet (make sure you get the dependencies right), as the agent won't fail unless you really start accessing the repository.