openresolv: new package

openresolv: new package

This patch added 'openresolv' package support. This tool
provides a dns management framework to track currently
available nameservers.

A key feature of this tool vs resolvconf is the ability to
manage multiple name server input configuration files and
generate the /etc/resolv.conf.  This is handy when you have
multiple dynamic communication paths providing nameserver
information.

REF: https://github.com/rsmarples/openresolv

Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>