Debian 9 is still in beta and doesn't have nginx.org builds yet, so we need to use the nginx package in Debian's repositories, and that required a bit of a different configuration. After official nginx.org builds are released we can revert this.
Updates from upstream config.
Since we're using a variable for the timezone for systemd-timesyncd anyways, we can also use it for PHP's config.
In Ubuntu 16.04 the package is now called just "php-fpm" and it makes more sense to just have this role be called that.