code: public VaadinForHeroku withFilterDefinition(final FilterDefinitionBuilder... filterDefs){
          checkVarArgsArguments(filterDefs);
          this.filterDefinitions.addAll(Arrays.asList(filterDefs));
          return self();
      }
docs: Add filter definitions to the server configuration.
  
  @param filterDefs the filter definition(s) to add.
  @since 0.3