Allow nested elements to pick up events before they get to ftscroller

This is basically a duplicate of https://github.com/ftlabs/ftscroller/pull/13 but up to date.

Using capturing instead of bubbling for events is a complete pain if you have anything inside a scroller than needs to respond to drag events. For example, I have audio players embedded in a scrollable page.

There is mention of issues with IE10 but I can't see any direct reference to the actual problem. The original use of event capturing was in the project from the beginning.