docs: public static Set<String> getSubsectionKeys(Properties properties) {
  		Set<String> retval = new HashSet<String>();
  		for (Object keyObj : properties.keySet()) {
  			String key = (String) keyObj;
  			if (key.indexOf(KEY_SEPARATOR) != -1) {
  				retval.add(key.substring(0, key.indexOf(KEY_SEPARATOR)));
  			}
  		}
  		return retval;
  	}