organize sidekiq jobs into logical queue names

https://assembly.com/coderwall/bounties/422

SearchSyncJob must use search_sync queue for uniqueness

SearchSyncJob depends on its queue being its own queue, because that is
how it enforces uniqueness
display 404 page: invalid route / record not found

- rescue_from ActionController::RoutingError doesn’t do anything
- `unless Rails.env.production?` made record not found work
- added tests! :-)
- new errors controller
- handle 422 & 500 errors with public pages
- annotate routes
Merge pull request #249 from codebender/fix/custom_404_page

Display custom 404 page: invalid route / record not found - Bounty #428
Merge pull request #247 from codebender/reorg_sidekiq_queues_422

Split up Sidekiq work across more specific queues. #422
Rebuilt the Coderwall basebox to fix several issues related to db not being ready and missing dependencies. Upgraded to Ruby 2.1.5. Added PhantomJS.