Add role for generating resque daemons and ansible handlers

* resque queues should be daemonized and run in the background, and
  managed through the OS. This makes them more relisient and easier to
  control.
* The task/handler in this role can be included by another role to
  generate a specific daemon for resque. This allows reusability of
  the daemon template by multiple apps, while still allowing a daemon
  to be defined for each queue.
Add role to specifically create Railsapp resque queues.

* the "default" one is a cache queue. But the queues are restarted
  after each deployment, and use the "resque" role to template the
  daemon and handler scripts.
Remove `rails_session*` environment variables, not used in Rails 4+