A MediaAsset represents an image or video file uploaded to Danbooru. It stores the metadata associated with the image or video. This is to work on decoupling files from posts so that images can be uploaded separately from posts.
Config
This directory contains configuration files for Danbooru.
To configure your Danbooru instance, copy danbooru_default_config.rb to danbooru_local_config.rb and edit it. See danbooru_default_config.rb for details.
The only file here that end users need to be concerned about is danbooru_default_config.rb. The rest of the files here are internal Rails-related configuration files that end users shouldn't need to edit.