code: @Override
      public List<String> getTypeNames(Map<TypeCache.TYPE_FILTER, String> filterMap) throws AtlasException {
          return typeSystem.getTypeNames(filterMap);
      }
docs: Return the list of type names in the type system which match the specified filter.
  
  @return list of type names
  @param filterMap - Map of filter for type names. Valid keys are CATEGORY, SUPERTYPE, NOT_SUPERTYPE
  For example, CATEGORY = TRAIT && SUPERTYPE contains 'X' && SUPERTYPE !contains 'Y'
  If there is no filter, all the types are returned