Changes

tsk24 Adds the user login and logout
The login form view and associated methods are added to check whether
you are logged in or not. Login and logout options are included in the
navbar. Adds an empty view when the user signs in. Fixes the path of the
search view to be absolute path. In addition, passwords are encoded in
the data scripts and errors in the table creation are fixed because
initializing the incremental keys is unnecessary. Comments in sql
scripts are translated to English. Defines security constraints for the
roles allowed for files based on the path /user/*.