Fix initialization when the Load Rails option is specified

[yujideveloper]

I want to use gems like SettingsLogic with Rails environements in the Shoryuken configuration file.
So, Rails must be loaded before loading the Shoryuken configuration file.

[phstc]

I want to use gems like SettingsLogic

@yujideveloper how would that let people to use --rails and load settings without using SettingsLogic or similar?

[pbernays]

ERB can't be processed if using something from the Rails project, eg.

queues:
  - [<%= Rails.application.config.some_setting %>, 1]
  - [<%= Settings.some_other_setting %>, 1]

because options are initialised before the Rails environment is loaded. That config file results in an uninitialized constant error.

[yujideveloper]

Sorry for slow response.
What I want to say is same as this comment.

[mariokostelac]

I think you are right, we have to load rails upfront. This functionality was somehow broken in last release.

[mariokostelac]

I think approach is good, but let's add some clarity to the codeflow.
load_rails loads config and initialises the logger in https://github.com/yujideveloper/shoryuken/blob/654536c35187ead505e8389c1635f58f9327c065/lib/shoryuken/environment_loader.rb#L102-L104. This makes initialize method messy because it's not clear why logger and options do not have to be loaded if we are loading rails.
I'd rather remove log line from load_rails (because it requires logger) and have initializer like:

load_rails if options[:rails]
initialize_options
initialize_logger
...

[yujideveloper]

@mariokostelac @phstc
Thank you for review.
I've updated codes. How do you think?

[mariokostelac]

I've checked manually against the codebase that was not able to have shoryuken upgraded because of loading config before rails and I am happy to say it does work!
Awesome work @yujideveloper.