Remove WiFi and Ethernet connectivity type options in RI.

Remove WiFi and Ethernet connectivity type options in RI.

- Replace with IPv4 and IPv6 options.
- Note that IPv6 is not currently supported
- Update C/C++ sample apps
- Update C/C++ unit tests
- Update several services files to support mod.

Change-Id: I086580d76665355d14cfa240347252cef969fa64
Signed-off-by: Doug Hudson <douglas.hudson@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/995
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Sakthivel Samidurai <sakthivel.samidurai@intel.com>
Reviewed-by: Joseph Morrow <joseph.l.morrow@intel.com>
Reviewed-by: Mandeep Shetty <mandeep.shetty@intel.com>
Reviewed-by: Erich Keane <erich.keane@intel.com>