closes #6430

closes #6368

database_rewinder seems to cause deadlocks in postgres and other
subtle bugs for us.

Spring is the recommended application preloader for rails

in features/desktop/aspect_navigation.feature:18 we quickly leave the page
before waiting for the request to finish. By making the HTTP call
synchronous we wait for it to finish before we reflect the change in the DOM,
thus giving Capybara a chance to wait for it. Also let Capybara wait longer.
This should random failures of the aforementioned cuke rarer.

* Dropped all references to Resque
* Moved all jobs under app/workers since that's the Sidekiq convention
* Renamed Jobs module to Worker to match new location
* Adapted all jobs to Sidekiq
* Replaced all enqueue calls with perform_async
* Dropped Resque hacks from specs and features, replaced with
  sidekig/testing in RSpec and sidekig/testing/inline in Cucumber
* Updated scripts to start a Sidekiq server
* Inline Sidekiq sinatra app
* Let Sidekiq create the actual Redis instance
* Workaround already initialized constant warnings in service models
* Resolved ToDo in one job definition by creating proper exception clases
  for some errors in receiving posts
* Added sidekiq section to configuration to make it completly
  configurable to the user
* Add Sidekiq middleware for clean backtraces
* Delay HttpMulti retry to give offline pods a chance to come back up
* Do not retry on GUID already taken and alike errors
* Be graceful about deleted posts in GatherOEmbedData

* Throw away old system
* Add new system
* Add new example files
* Replace all calls
* add the most important docs
* Add Specs
* rename disable_ssl_requirement to require_ssl
* cloudfiles isn't used/called in our code
* since community_spotlight.list is only used as enable flag replace it with such one and remove all legacy and irelevant codepaths around it
* die if session secret is unset and on heroku
* First basic infrastructure for version information

- `Rails.root` is a `Pathname`, so let's use `Rails.root.join`
- Clean up most of the remaining `File.join`s

-> https://makandracards.com/makandra/950-speed-up-rspec-by-deferring-garbage-collection

this speeds up tests from 9min 47sec to 9min 16sec on my machine
(6% improvement)

well that didnt work... Revert "try reconnecting after every cuke for postgres only to try and deal with travis issues"

This reverts commit 1604aedf.

bump capybara timeout to avoid timeout errorsdefine cucumber step to be pending so travis doesn't freak out

some cukes may be failing non deterministically, I think, do we bump the cuke timeout?