Project: mulestudio
Issue STUDIO-4346: DataMapper: "Generate Default" should provide feedback when successful 
When a user chooses to "Generate Default" in Datamapper, feedback should be provided when default generation has completed. See mockups for guidance (notice that the mockups represent a few phases of improvement): http://corp.wiki.mulesource.com/display/WP/Miscellaneous#Miscellaneous-DM%3AGenerateDefault
Story points: 5