Merge pull request #350 from puppetlabs/maint-os_refactor

(MAINT) Drop support for Windows Server 2008 R2.

Author: GSPatton

metadata.json

@@ -2,7 +2,7 @@
   "name": "puppetlabs-iis",
   "version": "8.1.0",
   "author": "puppetlabs",
-  "summary": "Manage IIS for Windows Server 2008R2, 2012, 2012R2 and 2016. Maintain application sites, pools, installation, and many other IIS settings.",
+  "summary": "Manage IIS for Windows Server 2012, 2012R2 and 2016. Maintain application sites, pools, installation, and many other IIS settings.",
   "license": "Apache-2.0",
   "source": "git://github.com/puppetlabs/puppetlabs-iis",
   "project_page": "https://github.com/puppetlabs/puppetlabs-iis",
@@ -17,7 +17,6 @@
     {
       "operatingsystem": "Windows",
       "operatingsystemrelease": [
-        "2008 R2",
         "2012",
         "2012 R2",
         "2016",