Moved dependency exif.dll to the References folder
Adjust all DNN/Telerik library  references to use the References folder
Reorganized reference DLL's so all external references are to files in a single folder.
Corrected older style for including DnnPlugins to use  JavaScript.RequestRegistration(CommonJs.DnnPlugins)
Merge pull request #1 from RichardHowells/tidyDNNdependencies

Tidy dnndependencies