feat: add youtube shorturl pattern

[adrienthiery]

Hi there !

Thanks for the contribution. 🙂

A few questions/requirements :

• Why is the new attribute called shortIconRef and not shortIcon ?
• Could you create 2 PRs please? One for the youtube shorturl pattern, the other for the shortIcon
• Would you mind adding at least a test for that in test/parser.js or modify all current tests so all tests pass ? (I had to modify the tests today because 2 of the test websites changed, so you will need to rebase your changes)
• I also added our eslint config on the newest version of master, please use this one to format the code 😅

Thanks a lot in advance !

[adrienthiery]

If you need help to refactor/redo your PR, don't hesitate to ask me, I can help you.

If you don't have the time to handle these changes, tell me as well and I can incorporate your changes in a new PR/version