added addtask.php jquery.createtaskvalid.js taskedit.php
createtask.php modified - final version page
etc.css - add styles for createtask.php
nav.css - correct z-index for right layout.
jquery-ui.css jquery.ui.datepicker.css - correct z-index for right layout
logpage.php - add form on login page.
reguser.php - correct SQL query for new table structure.