working on customer settings creation

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

core/src/main/java/de/srsoftware/umbrella/core/model/Document.java

@@ -169,6 +169,13 @@ public final class Document implements Mappable {
 		return !dirtyFields.isEmpty() || sender.isDirty() || customer.isDirty();
 	}
 
+	public boolean isDirty(String ... fields){
+		for (var field : fields){
+			if (dirtyFields.contains(field)) return true;
+		}
+		return false;
+	}
+
 	public boolean isNew(){
 		return dirtyFields.contains(ID);
 	}