PluginManager and added a cached plugin xml file to the PluginManager. Now we don't actually scan any assemblies on app startup
during plugin finding if none of the DLLs have changed. Added trace statements to the UmbracoModule for better benchmarking for
how long a full request takes to load from start to finish.
moves ResolveUrlsFromTextString to TemplateUtilities class and obsoletes other ones.
Fixes an issue if content cache is stored in codegen folder and not in med trust.
Updates the XmlDocument (IDocumentProperty) to always return a value with parsed {localLink} and resolved Urls and cache them so the parsing only happens once.
