Determines if the browser is IE and which version.

Browser.js

var Browser = (function() {
  'use strict';

  var version = -1;
  var isIE = false;
  var map = {
    '5.6': 6,
    '5.7': 7,
    '5.8': 8,
    '9': 9,
    '10': 10,
    '11': 11
  };
  var jscriptVersion = new Function('/*@cc_on return @_jscript_version; @*/')();

  if(jscriptVersion !== undefined || !!window.msCrypto) {
    isIE = true;
    version = map[jscriptVersion || '11'];
  }

  return {
    isIE: isIE,
    version: version
  };
}());