I'm currently using PHP 7.06 but can't seem to get past memory issues when upgrading to Magento 2.07. I read somewhere that PHP 7 has memory leakage issues, so I tried setting my PHP version back to 5.6. When I do that on the server, I get all sorts of errors when trying to open Magento front end or back end. Is there a setting somewhere that I need to change in order to change my PHP version from 7.06 to 5.6?