Add feature flag for sandbox environment

[lagoan]

Add feature flags beyond configuration values in order to control available behaviour in the sandbox environment. Initially, we will only need this to:

• Show a different logo for the tool showing that it is just a sandbox
• Disable the password reset functionality for seeded accounts

At this point, we can do something very simple as outlined here which can include simple logic.

In essence, we will be adding a class like

class Feature
  def self.enabled?(feature_name)
    case feature_name.to_sym
    when :sandbox
      # Should we allow super users to make changes in sandbox?
      Rails.env.sandbox? 
    else
      true
    end
  end
end

We can use simple if statements to block off code

if Feature.enabled?(:sandbox)
   # Code to be shown only in the sandbox environment
end

We can add different logic to provide super users Current.user.can_super_admin? different access in the application.

[pengyin-shan]

Pending task now:

• [ ] Use refactor instead of the if statement in feature_flag_helper
• [ ] Add RSpec test

[pengyin-shan]

@lagoan unfortunately, I don't think I can work on this in my last few hours with U of A...However, I think this could be a good first-time issue to assign to the new developer. I also suggest that the new developer contribute this back to the main codebase since the feature_flag_helper.rb file and our flag feature differentiate our code from the main codebase.