Add an option to provide another superclass other than ApplicationController

[hdoan741]

InheritedResource::Base inherits from ::ApplicationController and that's the source of a lot of issues for us during development. (We use it with ActiveAdmin). ApplicationController can be touched by many people and be reloaded but InheritedResource::Base is only loaded once. This leads to confusing behavior or breaking behavior with ActiveAdmin.

Also, we have an ApplicationController subclassing ActionController::API (for API applications), Inherited Resource/ActiveAdmin wouldn't work and we would have to change our ApplicationController code for it to work.

See this related issue in ActiveAdmin repo: activeadmin/activeadmin#2334

Request: Allowing InheritedResource::Base to inherit from a custom controller, or from ActionController::Base.
For example: It can inherit from an InheritedResource::BaseController, and that file is generated. It can subclass ApplicationController but user can change it to subclass a different controller if they want.