Fixes capturing on IE10 for Lumia 920

Addresses this bug: https://github.com/mobify/mobifyjs/issues/136

Initially, I could not replicate the bug on IE10 in a Windows 8 VM, but now the bug has surfaced on IE10 mobile for Lumia 920. We used to check for "interactive" as one test to determine if the DOM was ready, but in some variations of IE10, "interactive" is an incorrect state to poll.