Enable hot reload for rails dev environment

Work in progress

related to https://github.com/ruby-shoryuken/shoryuken/pull/756

By default Shoryuken does not support hot-reload for rails. If you want to enable hot-reload for the dev environment, you need to configure it as follows.

# config/initializers/shoryuken.rb
Shoryuken.enable_reloading = true

This assumes that you have rails reloading enabled (which is enabled in dev by default).