Add DocComments for function parameters

[chschneider]

This PR implements DocComment support for function parameters as proposed in
https://wiki.php.net/rfc/parameter-doccomments

[mvorisek]

Even if this harder to read syntax would be used, the return type/value cannot be commented. I personally do not support this feature.

[DanielEScherzer]

looking better

[TimWolla]

@chschneider Can you give this PR a fresh rebase onto the latest master to ensure the CI is current?

[TimWolla]

Can you add a test case for:

<?php

class Foo {
    public function __construct(
        /** $foo */
        public string $foo {
            /** setter */
            set(string $value /** $value */) {
                
            }
        }
    ) {}
}

to ensure that all the doc comments are correctly assigned if there's a property hook for constructor property promotion? The /** $foo */ should probably be applied to both the property and the parameter 🤔