static String makeKey(String moduleName, String key) {
		return moduleName + CompositeModule.OPTION_SEPARATOR + key;
	}
Tests for HierarchicalCompositeModuleOptionsMetadata.

@author Eric Bottard
spring-xd-module/src/test/java/org/springframework/xd/module/options/HierarchicalCompositeModuleOptionsMetadataTests.java