code: public String get(String exitingKey) {
          exitingKey = StringUtil.trimToEmpty(exitingKey).toLowerCase();
          Object clauses = getImpl(exitingKey);
          if (clauses == null) {
              return null;
          }
          return clauses.toString();
      }
docs: Retrieves the given key. Returns null if not set.
  If clause at key is a StringClause, return the string version of it.
  Will traverse sub-clauses to find the key.