Ensures that all config and state files are under HOMEBREW_PREFIX.
Configs are in #{etc}, state (leases and pids) in #{var}/dhcpd.
Prevents installed sample config files from clobbering existing
configs by renaming them to #{file}.sample.
Includes launchd plists for both DHCPv4 and DHCPv6.
Creates empty lease files so dhcpd will start on first use.
Added caveats explaining all of the above.
Signed-off-by: Adam Vandenberg <flangy@gmail.com>