code: def update_folder(folder_changes)
        req = build_soap! do |type, builder|
          if(type == :header)
          else
            builder.nbuild.UpdateFolder {
              builder.nbuild.parent.default_namespace = @default_ns
              builder.nbuild.FolderChanges {
                folder_changes.each do |fc|
                  builder[NS_EWS_TYPES].FolderChange {
                    builder.dispatch_folder_id!(fc)
                    builder[NS_EWS_TYPES].Updates {
                      # @todo finish implementation
                    }
                  }
                end
              }
            }
          end
        end
        do_soap_request(req)
      end
docs: Update properties for a specified folder
   There is a lot more building in this method because most of the builders
   are only used for this operation so there was no need to externalize them
   for re-use.
   @see http://msdn.microsoft.com/en-us/library/aa580519(v=EXCHG.140).aspx
   @param [Array<Hash>] folder_changes an Array of well formatted Hashes