an UmbracoHelper property to the PluginController class which will expose any methods needed by devs to retreive media or content.
Have updated UmbracoHelper with loads of new helpful methods and moved the Wrap methods to HtmlHelper extensions because this is purely to
do with rendering html (have written unit tests for it too).
Updated some 'library' methods to proxy calls to UmbracoHelper so we only have to maintain one set of code.
Added a convenience property to UmbracoContext to return the current NiceUrlProvider so you don't have to go through the RoutingContext to get it.
This allows us in the future to use any type of data source for the dictionary. Have obsoleted the old
ICultureDictionary in the macro engines project (where it doesn't belong anyways). The new one doesn't expose
the 'Language' property to the front-end because this is a business logic class which means designers can just delete
a whole language from the db by calling 'Delete' on the object !
