network: wire up dnsmasq option xmlns

This maps to XML like:

  <network xmlns:dnsmasq='http://libvirt.org/schemas/network/dnsmasq/1.0'>
    ...
    <dnsmasq:options>
      <dnsmasq:option value="foo=bar"/>
      <dnsmasq:option value="cname=*.foo.example.com,master.example.com"/>
    </dnsmasq:options>
  </network>

To dnsmasq config options

  ...
  foo=bar
  cname=*.foo.example.com,master.example.com

Reviewed-by: Laine Stump <laine@laine.org>
Signed-off-by: Cole Robinson <crobinso@redhat.com>

tests/networkxml2confdata/dnsmasq-options.conf

@@ -0,0 +1,18 @@
+##WARNING:  THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
+##OVERWRITTEN AND LOST.  Changes to this configuration should be made using:
+##    virsh net-edit default
+## or other application using the libvirt API.
+##
+## dnsmasq conf file created by libvirt
+strict-order
+except-interface=lo
+bind-dynamic
+interface=virbr0
+dhcp-range=192.168.122.2,192.168.122.254,255.255.255.0
+dhcp-no-override
+dhcp-authoritative
+dhcp-lease-max=253
+dhcp-hostsfile=/var/lib/libvirt/dnsmasq/default.hostsfile
+addn-hosts=/var/lib/libvirt/dnsmasq/default.addnhosts
+foo=bar
+cname=*.cloudapps.example.com,master.example.com