Prepare ConfigKit v0.1.1

override.go

@@ -188,7 +188,7 @@ func overlappingOverride(previous []Override, valid []bool, path Path) int {
 
 func pathContainsDirective(path Path) bool {
 	for _, segment := range path.segments {
-		if segment.key == "_configkit" {
+		if segment.key == directiveKey {
 			return true
 		}
 	}
@@ -205,7 +205,7 @@ func overrideDirectivePath(node *document.Node, path Path) (Path, bool) {
 	if node.Kind == document.Mapping {
 		for _, entry := range node.Mapping {
 			child := path.Key(entry.Key)
-			if entry.Key == "_configkit" {
+			if entry.Key == directiveKey {
 				return child, true
 			}
 			if found, ok := overrideDirectivePath(entry.Value, child); ok {