adding storage driver for windows

Author: Dave Try

manifests/init.pp

@@ -517,10 +517,16 @@
   }
 
   if $storage_driver {
-    assert_type(Pattern[/^(aufs|devicemapper|btrfs|overlay|overlay2|vfs|zfs)$/], $storage_driver) |$a, $b| {
-      fail translate(('Valid values for storage_driver are aufs, devicemapper, btrfs, overlay, overlay2, vfs, zfs.'))
+    if $::osfamily == 'windows' {
+      assert_type(Pattern[/^(windowsfilter)$/], $storage_driver) |$a, $b| {
+          fail translate(('Valid values for storage_driver on windows are windowsfilter'))
+      }      
+    } else {
+      assert_type(Pattern[/^(aufs|devicemapper|btrfs|overlay|overlay2|vfs|zfs)$/], $storage_driver) |$a, $b| {
+        fail translate(('Valid values for storage_driver are aufs, devicemapper, btrfs, overlay, overlay2, vfs, zfs.'))
+      }
     }
-  }
+  }  
 
   if ($bridge) and ($::osfamily == 'windows') {
       assert_type(Pattern[/^(none|nat|transparent|overlay|l2bridge|l2tunnel)$/], $bridge) |$a, $b| {