make badge, issuer, program undoably deletable.
Added Issuer#markAsDeleted() and Program#markAsDeleted().

Both of these cascade. No reason to really add a Badge.markAsDeleted()
since it just means setting the deleted property on it.
allow legacy documents to work w/ the new deletable models.
make deletion actually undoable.
allow badges to be undoably deleted, and add lame undo UI.
move undo page content and functionality into /admin page.
better naming of undo actions
don't show undo history section unless there's history to undo.
made test for Issuer#undoablyDelete() a lot better.
added tests for routes/undo.js.
Moved badge deletion client-side JS into common.js.

Also made it more generic so it'll be easy to use the same code for
deleting issuers and brograms.
remove script tag for nonexistent csol.js file.
added test for badge destroy route.
issuers can now be undoably deleted.
programs can now be undoably deleted.
Merge pull request #239 from toolness/issue-237-deletable-things

Make badge, issuer, program undoably deletable.