New Trait for decoding attribute in images

[pmoreno-rodriguez]

The decoding property of the HTMLImageElement interface provides a hint to the browser as to how it should decode the image. More specifically, whether it should wait for the image to be decoded before presenting other content updates or not.
With this trait you can add the decoding attribute to load images in an easy way. It basically works the same way as the 'loading' attribute (see Grav Docs), with async, sync and auto options. More info in Mozilla.org

[rhukster]

Lacking the additional default in system/config/system.yaml for the images.defaults.decoding value is not provided in the PR. Also with this additional property, there should be a correspoding entry in the system/blueprints/config/system.yaml blueprint.

Thanks!

[pmoreno-rodriguez]

Sorry for the oversight. Shortly, I will make the pull request from the admin plugin with the translations corresponding to the 'decoding' trait.

[rhukster]

As yoiuy can see the latest commit is now showing a bunch of failed tests. I think its becaues you the code is ALWAYS adding 'encoding="auto"' to every single link, even if you don't provide an encoding option.

[pmoreno-rodriguez]

Thank you very much for your help. Now the 'decoding' attribute behaves the same as 'loading' and I hope there is no problem.

[rhukster]

Looks good thanks!