static String qualifyProfile(String prefix, String profile) {
		return String.format("%s%s%s", prefix, HIERARCHICAL_PROFILE_SEPARATOR, profile);
	}
The composed module itself never needs to activate profiles. It's the submodules that should. The keys
returned here are special constructs that are decoded by {@link PrefixNarrowingModuleOptions}.
spring-xd-module/src/main/java/org/springframework/xd/module/options/HierarchicalCompositeModuleOptionsMetadata.java