Allow returning image type and file size from FastImage

[ishields]

FastImage provides file type and file size information. Both of these attributes are helpful when looking a the images on a website.

Ex 1: images that are extremely large or extremely small can be detected
Ex 2: images of unsupported file types can be detected.

I'd like to add a new option to allow returning this additional meta information from FastImage.

Note: PR is in progress and will be attached here.

[jaimeiniesta]

This is a great idea, @ishields 👍

I'm super busy these days but I'll try to review your PRs. Please ensure that you include specs for all your changes, these can help to understand them better as well.