lsb_release returns Arch instead of Archlinux

This fixes distrib_family() returning 'other' instead of 'arch'.
In Arch, supervisor config folder is supervisor.d
Arch bundles headers with base package

require/python.setuptools() doesn't need to raise when running arch linux.
Merge branch 'patch-2' of github.com:roblabla/fabtools
Merge branch 'patch-3' of github.com:roblabla/fabtools