Add 'image/webp' mime type support

[jficz]

Fixes #228

[skjnldsv]

Support is only 80% though 🤔
https://caniuse.com/webp

But I guess this will make people upgrade. All latest supported browsers works with them. Including mobile devices 🤷

[skjnldsv]

@cptMikky Please add a working webp example on cypress though :)

[aviallon]

Support is only 80% though thinking
https://caniuse.com/webp

It's 91.36% now, and growing. The camera app I use (OpenCamera) has an option to save pictures in webp, and this helped me reduce the file size of my pictures by 60%, which is non negligible.

Anything still holding back this pull request?

[skjnldsv]

cc @rullzer

[skjnldsv]

@cptMikky can you rebase? :)

[rullzer]

SO what will happen if you open this on safari? (since safari has no webp support)
Will it do boom?

[skjnldsv]

SO what will happen if you open this on safari? (since safari has no webp support)
Will it do boom?

Most likely display an "error loading xxx"

[rullzer]

So ok I don't know enough about the viewer to be honest.
But will it use the preview endpoint by default or just try to display the file as is?

[jficz]

let me see what I can do

[jficz]

@skjnldsv rebased, added Cypress test (I have no idea how that thing works so I just copy-pasted what was already there and updated it for webp)

[skjnldsv]

For 22 we can get this in as we dropped IE! 🚀

[skjnldsv]

Ah, this pr is not allowing me to rebase-push.
let me rebase on new pr