bug with delegate events in IE11

[mutex12]

Found a bug with delegate events in IE11.

The prefix "pre" assignment doesn't return "ms" but returns "webkit".

Causing the "matchSelector" to become undefined and this stops "delegateAction" working.

x-tag-core.js (bad)

prefix = (function () {
var keys = Object.keys(window).join();
var pre = ((keys.match(/,(ms)/) || keys.match(/,(moz)/) || keys.match(/,(O)/)) || [null, 'webkit'])[1].toLowerCase();

x-tag-components.js (good)

prefix = (function () {
var styles = win.getComputedStyle(doc.documentElement, ''),
pre = (Array.prototype.slice
.call(styles)
.join('')
.match(/-(moz|webkit|ms)-/) || (styles.OLink === '' && ['', 'o'])
)[1];

[mutex12]

This is a dup of #172.