Update Framework to support multiple dhpc ranges

Previously we only supported a single range - this was inadequate for
multiple interfaces.  Adding a second range so we can support
both usb and wifi tethering.

Also moving out of the zero-conf range as our dhcp client won't
accept ip addrs in that range (no nexus to nexus wifi action).

bug: 2537963
bug: 2533491
bug: 2538303
Change-Id: I600b421343c28c2f9839ed2076122ae3d0ff5d3d