Addition/readonly attribute

[basz]

This PR adds support for the readonly attribute, which differs from the disabled attribute

• A read-only field can't be modified, but, unlike disabled, you can tab into it, highlight it, and copy its contents.
• readonly is only relevant for type text, search, url, tel, email, number, password, and the date/time input types. It is also valid on <textarea>
• readonly is ignored for type hidden, range, color, checkbox, radio, file, button, submit and image

[simonihmig]

Looks good in general! But you have modified the template for the select element only for the vertical form layout, not horizontal and inline. Probably forgotten?

[basz]

That must be a mistake - select does not support read only anyway and its deprecated afaik.

Ill fix that soon

[simonihmig]

@basz Thanks a lot for this contribution! 👍

[basz]

You are welkome! Thanks for merging!