Migrated most of the functionality from RazorLibraryCore to UmbracoHelper and updated RazorLibraryCore to call

the methods in UmbracoHelper so we only have to maintain one set of code. Didn't port over the Wrap methods because
I need feedback on these as to what they do/are supposed to do.
Added the Media methods to UmbracoHelper using the media store stuff.

src/Umbraco.Web/DefaultPublishedMediaStore.cs

@@ -14,6 +14,9 @@ namespace Umbraco.Web
 	/// <summary>
 	/// An IPublishedMediaStore that first checks for the media in Examine, and then reverts to the database
 	/// </summary>
+	/// <remarks>
+	/// NOTE: In the future if we want to properly cache all media this class can be extended or replaced when these classes/interfaces are exposed publicly.
+	/// </remarks>
 	internal class DefaultPublishedMediaStore : IPublishedMediaStore
 	{
 		public virtual IDocument GetDocumentById(UmbracoContext umbracoContext, int nodeId)
@@ -60,6 +63,8 @@ namespace Umbraco.Web
 		internal IDocument ConvertFromSearchResult(SearchResult searchResult)
 		{
 			//TODO: Unit test this
+			//NOTE: we could just use the ExamineExtensions.ConvertFromSearchResult method but it will be faster to just
+			// use the data store in Examine cache.
 			throw new NotImplementedException();
 		}