Description of security groups configuration options

Configuration option = Default value	Description
[SECURITYGROUP]
enable_ipset = True	(BoolOpt) Use ipset to speed-up the iptables based security groups.
enable_security_group = True	(BoolOpt) Controls whether the neutron security group API is enabled in the server. It should be false when using no security groups or using the nova security group API.
firewall_driver = None	(StrOpt) Driver for security groups firewall in the L2 agent