Merge with upstream, then delete duplicate and unnecessary files

This will be controversial, and the PR is also very messy, so maybe this just becomes a discussion about what we want to do with Huboard.

I merged with upstream, then made memcached optional. CouchDB isn't required, so this eliminates both external service dependencies, and thus I ripped out anything related to Chef, Puppet, Vagrant, etc., since it's now entirely possible to just do a bundle+rackup to run this.

I also massively cleaned up the assets-directory, removing a bunch of duplicate vendored libraries. While ripping stuff out, I also ripped out Google Analytics, since it was hardcoded to the huboard.com domain.

I may have killed a bit too much, just from lack of understanding, but from my limited perspective, it seems like the entire development flow / asset pipeline could do with an overhaul, to prevent `application.js` from having to be committed.

Review, comments, suggestions etc.: @jduff @pallan @wisq @phoet @dneufeld 

/cc @kristianpd maybe?