Fix dataset module to support old browsers
Fix dataset module to support old browsers

At least IE10 does not support the elm.dataset property, so we must use
elm.removeAttribute and elm.setAttribute instead.

snabbdom/snabbdom,paldepind/snabbdom,snabbdom/snabbdom,paldepind/snabbdom,staltz/snabbdom,staltz/snabbdom,staltz/snabbdom,snabbdom/snabbdom,snabbdom/snabbdom