network/dhcp: Update deprecated option dnsmasq_server

dnsmasq_dns_server is deprecated since approx. 1 year,
the new option is dnsmasq_dns_servers (an array of DNS IP).

See:
https://github.com/openstack/neutron/commit/a269541c603f8923b35b7e722f1b8c0ebd42c95a

Change-Id: I752fc0c6b176d36e9fc5d35609e533f2659afdd4
(cherry picked from commit 145d228d0fd7955b140adf46aab856d08ada8b89)
network/controller: Remove duplicate parameters

Neutron_db_* parameter and ks_keystone_admin_* are duplicated
in the params list, let's remove them.

Change-Id: Icb91d790712942addd3982f78263134041ddad15
(cherry picked from commit 171fb00d602fe7a79f676bc681687cd538ee3fa8)
Merge pull request #735 from enovance/fix-dupp

Update deprecated option for dnsmaq + remove dupp params