def resolve_respond_timeout(ttr)
      if ttr.respond_to?(:queue_respond_timeout)
        resolve_respond_timeout(ttr.queue_respond_timeout)
      elsif ttr.is_a?(Integer) # numerical
        ttr
      else # default
        Backburner.configuration.respond_timeout
      end
    end
Resolves job respond timeout based on the value given. Can be integer, a class or nothing

@example
resolve_respond_timeout(1000) => 1000
resolve_respond_timeout(FooBar) => <queue respond_timeout>
resolve_respond_timeout(nil) => <default respond_timeout>