How do you set image path without config.rb?

Hello!

Thank you for this great module!

However, how do you set image path without config.rb? I want to configure `images_path` and `http_images_path` in order to have correct image path in my output CSS files.

No file, test, or entry point is named in the issue. Start by locating the plugin's configuration handling and clarify how images_path and http_images_path can be set without config.rb; done means the documented approach produces the intended image paths in the output CSS.

Written by the indexing model from the issue text.