header::create(), header::set(), header::link()

[Sebastiaan Andeweg]

I really like this new method header::create()! Looking forward to use it.
https://github.com/getkirby/toolkit/blob/develop/lib/header.php#L77

The name, however, collides a bit with header::created(). I would like to suggest header::set() as an alias / rename.

Also, from reading the code, the function never actually sets the header with header(), it only returns it as a string. You can't, however, use it like header(header::create(['a'=>'b', 'c'=>'d']));: PHP will complain ('Warning: Header may not contain more than a single header, new line detected').
I was wondering how it was mend to be used.

And finally, I would like to easily send a HTTP Link header, something like this would be nice:

header::link('/webmention', 'webmention');
// Link: </webmention>; rel="webmention"

header::link([
  '/micropub' => 'micropub',
  'https://indieauth.com/auth' => 'authorization_endpoint',
  'https://tokens.indieauth.com/token' => 'token_endpoint',
]);
// Link: </micropub>; rel="micropub"
// Link: <https://indieauth.com/auth>; rel="authorization_endpoint"
// Link: <https://tokens.indieauth.com/token>; rel="token_endpoint"

I can try something and send a PR if you're interested :)