Added in a little hack to get it working in IE9.

I think a better solution is called for, but this is more of a proof of concept for IE.

Squash this commit out before sending a PR upstream.
Use a generic addEvent method that works cross browser.
WIP - get things working properly cross browser

1. Back button not working
2. need to attach event to body, not window 
	- doesn't seem to help with 1., and might break things in other browsers?
Simplified event handling code + got popstate working.

Seems to work, not sure about detaching..
Use `history.location` before `document.location`.

Changes from @devote. We need to look at `history.location` when it exists (for polyfilled browsers, as `document.location` will included a hash.
Merge remote-tracking branch 'upstream/master' into ie-support
Merge remote-tracking branch 'upstream/master' into ie-support

Conflicts:
	index.js
Merge branch 'ie-support'

Conflicts:
	index.js