Not install sinatra and slim on client

[alxgsv]

Hello, my app built on Rails so it is strange for me to have Sinatra in Gemfile.lock to handle Sidekiq failures.

Sinatra is great, btw.

Does it possible to somehow avoid this dependency on client? (I have separate monitoring app that loads Siqekiq::Web's Sinatra).

[mhfs]

@LongMan I think you are right. sidekiq doesn't depend on them and sidekiq-failures shouldn't as well.

Would you be willing to send a pull-request over? If so, please also remove dependency of sprockets since sidekiq doesn't use it anymore.

[alxgsv]

I'll do my best if I can :-)

[alxgsv]

Opened PR.