config mvc-dispathcer-server.xml
add test should_return_itemList
add ItemController
modify getItems method
add test should_return_itemList
add test should_return_item_when_input_id
modify getItem method
add test should_delete_item_when_input_id
modify deleteItem method
overwrite toString method
add test should_insert_item
modify insertItem
add test should_update_item
modify updateItem method