DDF-745 - Adjusting the installer to only show the application page when in customize mode.

-minor adjustments to ui while I was in.
--Replaced arrow text characters with font-awesome arrows.
--removed the previous button on the last page
--adding a loading spinner when hiding the application tree (only when not customizing)
-removed datatables from our javascript deps.
Merge pull request #31 from McLucas/feature/DDF-745