Added the SecurityGroup attribute to servers result
diff --git a/openstack/compute/v2/servers/results.go b/openstack/compute/v2/servers/results.go
index d63d7c8..1b22f21 100644
--- a/openstack/compute/v2/servers/results.go
+++ b/openstack/compute/v2/servers/results.go
@@ -139,6 +139,9 @@
 	// AdminPass will generally be empty ("").  However, it will contain the administrative password chosen when provisioning a new server without a set AdminPass setting in the first place.
 	// Note that this is the ONLY time this field will be valid.
 	AdminPass string `json:"adminPass" mapstructure:"adminPass"`
+
+	// SecurityGroups includes the security groups that this instance has applied to it
+	SecurityGroups []map[string]interface{} `json:"security_groups" mapstructure:"security_groups"`
 }
 
 // ServerPage abstracts the raw results of making a List() request against the API.