Added middle and right mouse button support.

By default Hammer had a check for ev.button === 0 (left-button only).

Now this can be configured by passing in mouseButtons array to Hammer options object like so:

Hammer(element, {
    // Left, mid and right buttons allowed
    mouseButtons: [0,1,2]
});

PS: Handle and preventDefault the "contextmenu" event yourself for right-click dragging with Hammer to work properly in your document. Example:

document.documentElement.addEventListener("contextmenu", function (ev) { ev.preventDefault(); });