Add zend opcache template to enable it

Add zend opcache template to enable it. This template is based on the opcache.ini in the php54-php-pecl-zendopcache-7.0.2-4.el6.x86_64.
`=1M` to be consistent with https://github.com/openshift/origin-server/blob/master/cartridges/openshift-origin-cartridge-php/usr/5.3/etc/php.d/apc.ini.erb#L41