-Added support for the Real-ESRGAN Anime upscaler.
This upscaler is much faster and yields much better results than waifu2x, so it is recommended to use it instead. Other notes:
-Real-ESRGAN only supports scale factors between 2-4
-If the scale factor is set to 4 it will use a slower model that gives slightly better results. This is better for images.
-It is actually feasible to upscale videos now because of how fast it is (but 4x scale factor not recommended).