Latest commit 32094dc Nov 23, 2016 @mislav mislav Ensure `ready` always fires on IE 10
IE 10 is reported to have weird states re: `readyState` and regarding
DOMContentLoaded has already been fired or not. In case we are too late
to register the DOMContentLoaded handler (the event already fired), also
register a `window.onload` handler as fallback.

Closes #1240, ref. #1235