support label and annotation selection in replacement targets

kyaml/resid/resid.go

@@ -4,6 +4,7 @@
 package resid
 
 import (
+	"reflect"
 	"strings"
 )
 
@@ -129,3 +130,9 @@ func (id ResId) EffectiveNamespace() string {
 	}
 	return id.Namespace
 }
+
+// IsEmpty returns true of all of the id's fields are
+// empty strings
+func (id ResId) IsEmpty() bool {
+	return reflect.DeepEqual(id, ResId{})
+}