Do not use default LXC network in gate
Do not use default LXC network in gate

hpcloud-b4's eth0 uses 10.0.3.0/24, which overlaps with the
lxc_net_address default.  This commit sets the following in the gate:

lxc_net_address: 10.255.255.1
lxc_net_netmask: 255.255.255.0
lxc_net_dhcp_range: 10.255.255.2,10.255.255.253

At some point we'll need to implement a mechanism to determine valid
lxc_net_address value which will not overlap with an IP already
assigned to the host.

Change-Id: Ib4df050be2d8734c636b6adcc81a53258796b5a8
(cherry picked from commit 238c06baa89fe62bc0d70166cb08234ff33623e4)

VaneCloud/openstack-ansible,yanyao/openstack-deployment,yanyao/openstack-deployment,VaneCloud/openstack-ansible,yanyao/openstack-deployment,yanyao/openstack-deployment,VaneCloud/openstack-ansible