support using icmpv6 (protocol num 58) in the protocol option, when creating
a security group rule.At this time, port_range_min/port_range_max represent
icmpv6 type/code, and you can use only port_range_min to specify just one type.
eg:neutron security-group-rule-create --direction ingress \
--ethertype ipv6 --protocol icmpv6 --port-range-min 134 SECURITY_GROUP
ApiImpact
DocImpact
Partial-Bug:#1427973
Change-Id: Ide4f7476cdb8a4f04f72983917ce7dbfc7be90a5