Error reporting

Sneakers allows to register error reporters. Some agents like sentry-raven call #to_json on context object. Ensure to filter out delivery_info from context before passing it to the sentry-raven. Otherwise #to_json causes SystemStackError: stack level too deep error when attempts to serialize instance of Bunny::Session which comes with delivery_info. The issue in Sneakers repo.

Example:

# /config/initializers/sneakers.rb
Sneakers.error_reporters << proc do |error, _worker, context|
  Raven.capture_message(error, extra: context.except(:delivery_info))
end