Provision wheel group on FreeBSD servers
Summary:
The 'wheel' group contains all ops and root account.
It allows to use the su command on BSD machines.
Fixes T1778.
Test Plan: Tested on Windriver
Reviewers: dereckson
Reviewed By: dereckson
Maniphest Tasks: T1778
Differential Revision: https://devcentral.nasqueron.org/D2825