[refs #72] Gratuitious amounts of jiggerypokery to coerce Wordpress into working. The process running WordPress needs to have the same uid as the files it creates (see http://wordpress.stackexchange.com/a/108990), so the best solution is to create an FPM pool per PHP app (which is actually more secure in any case)
[refs #72] Updating the AkvoSites provisioning to use the new PHP pools