Update module to include new API

Hi, there is a new interface available for BugHerd. To update to the new API we simply need to change lines 34-39 in bugherd.module to the following:

(function (d, t) {
var bh = d.createElement(t), s = d.getElementsByTagName(t)[0];
bh.type = 'text/javascript';
bh.src = '//www.bugherd.com/sidebarv2.js?apikey={$api_key}';
s.parentNode.insertBefore(bh, s);
})(document, 'script');

Patch to follow shortly....