Add Missing Neutron v2 Protocol Constants

This commit adds two missing neutron v2 protocol constants. It
also re-arranged the ordering to alphabetical.
diff --git a/openstack/networking/v2/extensions/security/rules/requests.go b/openstack/networking/v2/extensions/security/rules/requests.go
index 83120c4..59ba721 100644
--- a/openstack/networking/v2/extensions/security/rules/requests.go
+++ b/openstack/networking/v2/extensions/security/rules/requests.go
@@ -49,27 +49,29 @@
 const (
 	DirIngress        RuleDirection = "ingress"
 	DirEgress         RuleDirection = "egress"
-	ProtocolTCP       RuleProtocol  = "tcp"
-	ProtocolUDP       RuleProtocol  = "udp"
-	ProtocolICMP      RuleProtocol  = "icmp"
+	EtherType4        RuleEtherType = "IPv4"
+	EtherType6        RuleEtherType = "IPv6"
 	ProtocolAH        RuleProtocol  = "ah"
 	ProtocolDCCP      RuleProtocol  = "dccp"
 	ProtocolEGP       RuleProtocol  = "egp"
+	ProtocolESP       RuleProtocol  = "esp"
 	ProtocolGRE       RuleProtocol  = "gre"
+	ProtocolICMP      RuleProtocol  = "icmp"
 	ProtocolIGMP      RuleProtocol  = "igmp"
 	ProtocolIPv6Encap RuleProtocol  = "ipv6-encap"
 	ProtocolIPv6Frag  RuleProtocol  = "ipv6-frag"
 	ProtocolIPv6ICMP  RuleProtocol  = "ipv6-icmp"
 	ProtocolIPv6NoNxt RuleProtocol  = "ipv6-nonxt"
 	ProtocolIPv6Opts  RuleProtocol  = "ipv6-opts"
+	ProtocolIPv6Route RuleProtocol  = "ipv6-route"
 	ProtocolOSPF      RuleProtocol  = "ospf"
 	ProtocolPGM       RuleProtocol  = "pgm"
 	ProtocolRSVP      RuleProtocol  = "rsvp"
 	ProtocolSCTP      RuleProtocol  = "sctp"
+	ProtocolTCP       RuleProtocol  = "tcp"
+	ProtocolUDP       RuleProtocol  = "udp"
 	ProtocolUDPLite   RuleProtocol  = "udplite"
 	ProtocolVRRP      RuleProtocol  = "vrrp"
-	EtherType4        RuleEtherType = "IPv4"
-	EtherType6        RuleEtherType = "IPv6"
 )
 
 // CreateOptsBuilder is what types must satisfy to be used as Create