Words manage. Insert/Update/Filter and Search

# Words Manage (Admin)
* Functions:
    * Insert
    * Update
    * Manage
    * Search & filter
* Files:
    * app/Controller/WordsController.php
    * app/Model/Word.php
    * app/View/Words/admin_index.ctp
    * app/View/Words/admin_edit.ctp
Cake PHP recommends calling the create function to re-initialize a model before saving a new record
Sorry, viết như giờ ok nhá :D