src/main/java/de/jformchecker/FormChecker.java
private void setupConfig() {
		if (config == null) {
			if (tempFormBuilder == null) {
				tempFormBuilder = new BasicFormBuilder();
			}
			if (tempProperties == null) {
				tempProperties = new MinimalMessageSource();
			}
			config = new FormCheckerConfig(tempProperties, tempFormBuilder);
		}
	}
private void setupConfig() {
		if (config == null) {
			if (tempFormBuilder == null) {
				tempFormBuilder = new BasicFormBuilder();
			}
			if (tempProperties == null) {
				tempProperties = new MinimalMessageSource();
			}
			config = new FormCheckerConfig(tempProperties, tempFormBuilder);
		}
	}
set up the config-object for formchecker (handles absence of properties
and formBuider)