fix for issue 21 "Autoloading and XmlLens loading fails"

error "change from 'absent' to 'present' failed: Could not set 'present' on ensure: uninitialized constant XmlLens"

lib/puppet/type/xmlfile.rb

@@ -208,7 +208,7 @@ def should_content # Ape the name from property::should
     end
 
     res.each do |resource|
-      process = XmlLens.new(xml_content, resource[:changes], resource[:onlyif])
+      process = PuppetX::VoxPupuli::Xmlfile::Lens.new(xml_content, resource[:changes], resource[:onlyif])
       xml_content = process.evaluate
     end