Change Rollbar::Configuration#use_sucker_punch and Rollbar::Delay::SuckerPunch to match previous async API changes.

Added SuckerPunch spec
More explicit `Rollbar::Configuration#use_sidekiq` signature
Added guard and deprecation warning 

..around `Rollbar::Configuration#use_sidekiq=` and `Rollbar::Configuration#use_sucker_punch=` to match new syntax.