Set attribute whitelists for Knife-Zero

This prevents all attributes to be written in the node files. We don't
want that data stored in git.
See https://knife-zero.github.io/40_configuration/

.chef/config.rb

@@ -11,3 +11,24 @@ local_mode                true # Chef local mode, replacing Solo
 cookbook_copyright     'Kosmos'
 cookbook_license       'none'
 cookbook_email         'mail@kosmos.org'
+
+# Knife-Zero config, see https://knife-zero.github.io/40_configuration/
+# Prevent attributes from being saved to the node files
+knife[:automatic_attribute_whitelist] = %w[
+  fqdn
+  os
+  os_version
+  hostname
+  ipaddress
+  roles
+  recipes
+  ipaddress
+  platform
+  platform_version
+  cloud
+  cloud_v2
+  chef_packages
+]
+knife[:default_attribute_whitelist] = []
+knife[:normal_attribute_whitelist] = ['knife_zero']
+knife[:override_attribute_whitelist] = []