These are just warnings that won't effect the overall functionality of the page.
If you receive errors regarding function deprecation, the following two methods can tell PHP to simply stop mentioning deprecated functions or coding:
You can add the following line to your php.ini file:
error_reporting = E_ALL & ~E_DEPRECATED & ~E_NOTICE
Or you can add the following line to any page that shows the message:
<?php
error_reporting(E_ALL & ~E_DEPRECATED & ~E_NOTICE);
?>