migrate/issue2807.ns6_5: moved to networks DB. Was #2807

Fixes annoying ERROR message in /var/log/messages, if networks DB is
still not initialized. This happens once, during system-init.
resolv.conf: fix multiple "nameserver" expansion. Refs #2918

Add also the "search" directive. If it is missing, ifup-post script
adds it automatically, invoking set_hostname function, defined in
/etc/sysconfig/network-scripts/network-functions.