fix(primary-ip): list does now allow to output IP column

Since IP is a *hcloud.PrimaryIP, AddAllowedFields() only adds columns for primitive types and a field function for IP was missing, you were not able to output the IP column using output flags.

Closes #591

internal/cmd/primaryip/list.go

@@ -38,6 +38,13 @@ var ListCmd = base.ListCmd{
 	OutputTable: func(client hcapi2.Client) *output.Table {
 		return output.NewTable().
 			AddAllowedFields(hcloud.PrimaryIP{}).
+			AddFieldFn("ip", output.FieldFn(func(obj interface{}) string {
+				primaryIP := obj.(*hcloud.PrimaryIP)
+				if primaryIP.Network != nil {
+					return primaryIP.Network.String()
+				}
+				return primaryIP.IP.String()
+			})).
 			AddFieldFn("dns", output.FieldFn(func(obj interface{}) string {
 				primaryIP := obj.(*hcloud.PrimaryIP)
 				var dns string