Base class for creating [ImageFormatLoader] extensions (adding support for extra image formats). The engine supports multiple image formats out of the box (PNG, SVG, JPEG, WebP to name a few), but you can choose to implement support for additional image formats by extending this class. Be sure to respect the documented return types and values. You should create an instance of it, and call [method add_format_loader] to register that loader during the initializaiton phase. Returns the list of file extensions for this image format. Files with the given extentions will be treated as image file and loaded using this class. Loads the content of [param fileaccess] into the provided [param image]. Add this format loader to the engine, allowing it to recognize the file extensions returned by [method _get_recognized_extensions]. Remove this format loader from the engine.