Adding autocomplete values of to input/select/textarea

[codepo8]

https://html.spec.whatwg.org/multipage/forms.html#inappropriate-for-the-control

This allows for lots of great auto completion for forms.

[msftclas]

Hi @codepo8, I'm your friendly neighborhood Microsoft Pull Request Bot (You can call me MSBOT). Thanks for your contribution!

This seems like a small (but important) contribution, so no Contribution License Agreement is required at this point. Real humans will now evaluate your PR.

TTYL, MSBOT;

[aeschli]

Thanks @codepo8, nice work!

[aeschli]

@codepo8 Just FYI, the HTM language service (including your contributions) are now in its own node module: https://github.com/Microsoft/vscode-html-languageservice.