Require Puppet >= 3.6.0

Mostly due to breaking changes in how the `puppet module list` Face works.

README.md

@@ -9,6 +9,9 @@ A Puppet Face and plugin built on the [YARD Documentation Tool](http://yardoc.or
 Installation
 ------------
 
+So far, this module has been developed against Puppet 3.6.x.
+It will not work with earlier versions.
+
 Currently, just `git clone` directly into the Puppet `modulepath`.
 Ensure the `yard` and `rgen` gems are installed.
 If running Ruby 1.8.7, ensure the `backports` gem is installed.

lib/puppet/face/yardoc.rb

@@ -74,6 +74,9 @@ Puppet::Face.define(:yardoc, '0.0.1') do
       require 'puppetx/yardoc/yard/plugin'
       opts = args.pop
 
+      # NOTE: The retrun value of the `module` Face seems to have changed in
+      # 3.6.x. This part of the code will blow up if run under an earlier
+      # version of Puppet.
       modules = Puppet::Face[:module, :current].list
       module_list = modules[:modules_by_path].values.flatten
 

metadata.json

@@ -7,6 +7,12 @@
   "source": "",
   "project_page": null,
   "issues_url": null,
+  "requirements": [
+    {
+      "name": "puppet",
+      "version_requirement": ">= 3.6.0"
+    }
+  ],
   "dependencies": [ ]
 }