Dropbox authentication.
Populate file list.
Use query.
Fix bug: trailing slash in Dropbox redirected URL.
Tidy up hash after Dropbox auth.
URI encode hash.
Move url tidying.
on_hash_change event.
Drop history and hash.

History.js had too many bugs wrt hashes and events.
replaceState and pushState don't work for removing hashes.
Events double fire for actual clicks vs replaceState/pushState.
Events don't fire for clicks that remove the hash.
Switch to ender.
Initial work on dearmoring.