* Add minlength attribute
* Update required attribute to a boolean attribute

* Add allowfullscreen attribute
* Set sandbox to boolean attribute
* Add valid values for the sandbox attribute

option is a child of datalist, not an attribute

* Add onlanguagechange
* Remove onblur, onerous, onfocus, onload (existing global attributes)
* Move onresize and onscroll to global event handlers

Add download attribute (now widely supported.)
Remove media attribute (only valid on style and link elements)

It is not included in the list of global attributes for either W3C
HTML5/5.1 or WhatWG Living Standard.

There was a proposal for an inert keyword but it was dropped
https://github.com/whatwg/html/commit/5ddfc78b1f82e86cc202d72ccc752a0e15
f1e4ad

The prefixless version should always be last, so that the older
prefixed implementation (if different) doesn’t win out in the cascade.
Especially now other browsers (Edge) support the webkit version as well.

Removed -o- as that was only used by Opera 11.5, which hasn’t been the
current version since I worked there. Presto users were quickly
auto-updated to Opera 12, and now Opera uses Blink.

The element is no longer part of the API. It is no fully JavaScript
based.

* svg
* menuitem (already in IntelliSense)

* bdo
* data
* embed
* main
* rb, rp, rt, rtc, ruby
* s
* source
* template
* track
* u
* wbr

* acronym
* big
* strike
* tt
* frame
* frameset
* noframes

Add ARIA role values and ARIA 1.1 attributes

…including adding undefined value to orientation

Add HTML aria attribute autocomplete

syntax highlighting for c++: 'value' keyword removed.

fixes the internal builds

Fixes #320