code: function inherit(subType, superType) {
      var prototype = createObject(superType.prototype);
      prototype.constructor = subType;
      subType.prototype = prototype;
  }
docs: Provide a simple inheritance in prototype-oriented.<br>
  Caution :
  Don't overwrite the prototype of child constructor.
  
  @param {function} subType Child constructor
  @param {function} superType Parent constructor
  @memberof tui.util
  @example
  //-- #1. Get Module --//
  var util = require('tui-code-snippet'); // node, commonjs
  var util = tui.util; // distribution file
  
  //-- #2. Use property --//
  // Parent constructor
  function Animal(leg) {
  this.leg = leg;
  }
  Animal.prototype.growl = function() {
  // ...
  };
  
  // Child constructor
  function Person(name) {
  this.name = name;
  }
  
  // Inheritance
  util.inherit(Person, Animal);
  
  // After this inheritance, please use only the extending of property.
  // Do not overwrite prototype.
  Person.prototype.walk = function(direction) {
  // ...
  };