Install PHP 5.3 on CentOS 5.11

PHP 5.3 on CentOS/RHEL 5.11 via Yum

Webtatic has now ended support for PHP 5.3, and suggests either:

* Upgrade RHEL/CentOS to 6.7, so that you can install php 5.3.3, which is still supported by those distributions.
* Upgrade PHP to the latest available version, which Webtatic supplies PHP 5.5 for EL5