[Feat Request] Validate partials

[hefler]

It would be nice if this extension also validated HTML partials (without html, head and body tags).

All this tags could be "implied" if not present in an HTML document.

[celian-rib]

I @hefler , do you have a file as an example ?

[hefler]

Let's say this is an HTML file called partials.html.

<div>
    <header>
        <h1>HTML5 Partials</h1>
        <h2>Small bits of HTML</h2>
    </header>
    <main>
        <p>This is a perfect "validatable" piece of HTML code that fails get validated.</p>
        <p>Yet validating partials such as this can be useful. :)</p>
    </main>
</div>

Then in the extension preferences having something like:

Validate partials as:

• [x] HTML5
• [ ] XHTML
• [ ] HTML4