code: public List<String> findRedundantDeclarations() {
          List<String> result = new ArrayList<String>();
          for(ThemeTreeNode node: rootNode.childMap.values()) {
              findRedundantDeclarations(result, node);
          }
          Collections.sort(result);
          return result;
      }
docs: Returns a list of redundant theme entries in this theme. A redundant entry means that it doesn't need to be
  specified because there is a parent node in the hierarchy which has the same property so if the redundant entry
  wasn't there, the parent node would be picked up and the end result would be the same.
  @return List of redundant theme entries