added the 'gui' message type
FF CSP fix: posted GUIs now hosted by httpserver (with horrible, mustchange hack)
gui input now expands/contracts when it has content
switched iframeSandbox to a postMessage injection api
added guiplies (gui replies)
added guis to reply count
updated gui posts to have play overlay btn and x btn on top right
gui form preview now uses same control as posted guis
Merge pull request #95 from pfraze/app-post

'gui' posts