[Geany] HTML5 attributes

[Ross McKay]

Sorry, forgot to do the new attributes. I've not bothered with the fleet
of ARIA[*] attributes here, as I haven't spent any time looking at ARIA
and suspect that it's a moveable feast at present anyway.

async autocomplete autofocus contenteditable contextmenu draggable
formaction formenctype formnovalidate formtarget list manifest max min
novalidate pattern ping placeholder required reversed role sandbox
scoped seamless sizes spellcheck srcdoc step

* http://www.w3.org/WAI/PF/aria/
-- 
Ross McKay, Toronto, NSW Australia
"My old man told me one time, you never get wise, you only get older"
- Dandy Warhols