php-fpm is broken on centos for the moment, use the fork until it gets fixed
Add package support for web_nginx

Setting `node['zabbix']['web']['install_package'] = true` will install from
package. This will include the database-specific (mysql or postgres) package
that installs the correct PHP dependencies, including database driver.
Install web from package on nginx.

The username is case-sensitive in 2.2 apparently.