Imports that fail because one of the import workers fails to complete should not go to a ready state. They should be stuck in loading until the import completes successfully.
Fixes for the new importing logic:

* Blobs now track the BlobImports and KeyCreators working on them, much like
  Commits track the CommitImporters/BlobImporters working on them. Blobs now
  have a loading column that works identically to Commit.
* Upgraded blobs_keys to a full-blown model, a la CommitsKey, and used more
  straightforward ActiveRecord to do creation and deletion of these records,
  in order to avoid duplicate key errors.
* Fixed a bug where blobs_keys entries would be incorrectly deleted.
* Fixed a bug or two regarding the correctness of the Commit worker list.
More robust way of loading blobs
Fixes commit spec for DST
Adds cookies to save preferences on homepage

Conflicts:
	Gemfile
	Gemfile.lock
Removes final references to keys_cached
Better cookies
Page titles based on context
Makes home index filter hideable:
Adds sidekiq-failures
Restructures javascript
Changes redirect of projects_controller back to project
Adds affix to all pages

Conflicts:
	app/assets/javascripts/application.js.coffee
Uses a self-generated unique ID instead of Sidekiq JID

Conflicts:
	lib/sidekiq_worker_tracking.rb
Two small fixes
Fixes z-index of filter bar
Adds cookies to request translation form
Case insensitive filter
added Brewfile and updated README.md
Fixes cookies for request translation bug