NEWOPS-1083 Look in the right place.

The old code was actually relying on a global aged Hiera 3 configuration that Mat had deliberately left lying around in `/etc/puppetlabs/puppet/hiera.yaml`. This is liable to stop working at some point so let's just read the options from the environment's default options.

lib/puppet/functions/eyaml_tools/utils.rb

@@ -10,11 +10,11 @@ def ensure_config
     unless @config_done
       c = hiera_config
       raise Puppet::ParseError, 'no Hiera config found' unless c
-      eyaml_config = c[:eyaml]
-      raise 'no :eyaml section found in Hiera config' unless eyaml_config
+      eyaml_config = c['defaults']['options']
+      raise 'no defaults.options section found in Hiera config' unless eyaml_config
       eyaml_config.each do |key, value|
         Puppet.debug "EyamlTools: setting #{key} to #{value}"
-        Hiera::Backend::Eyaml::Options[key] = value
+        Hiera::Backend::Eyaml::Options[key.to_sym] = value
       end
       @config_done = true
     end