Switch to the IUS package repository

Adjust package names to match. php-fpm will not launch at this time as it expects an apache user to be present. We'll take care of that shortly.
Additional PHP packages that we want
Remove php54-memcache package from provisioning

Backing off on the decision to use memcache for now, especially because we're starting with a single server and APC will likely serve our purposes better at first.
Create a devserver definition for loading things like xdebug

There are some things that likely shouldn't end up on production servers. At some point we'll split provisioning up to create these different environments and things like xdebug should be left behind.
Switch to the Remi repos for our PHP and MySQL stuff

Per recommendation from @thelastcicada, these are working out much nicer so far.