Parsing states from an XML file

The file we will be parsing is the following (test.xml in source code downloads):

<?xml version="1.0" ?>
<STATES>
<MENU>
<TEXTURES>
  <texture filename="assets/button.png" ID="playbutton"/>
  <texture filename="assets/exit.png" ID="exitbutton"/>
</TEXTURES>

<OBJECTS>
  <object type="MenuButton" x="100" y="100" width="400" 
  height="100" textureID="playbutton" numFrames="0" 
  callbackID="1"/>
  <object type="MenuButton" x="100" y="300" width="400" 
  height="100" textureID="exitbutton" numFrames="0" 
  callbackID="2"/>
</OBJECTS>
</MENU>
<PLAY>
</PLAY>

<GAMEOVER>
</GAMEOVER>
</STATES>

We are going to create a new class that parses our states for us called StateParser. The StateParser class has no data members, it is to be used once in the onEnter function of a state and then discarded when it goes out of scope. Create a StateParser.h file and add the following...