Making the module a little more compliant with the Zend Framework Coding Standards

**Ref: http://framework.zend.com/wiki/display/ZFDEV2/Coding+Standards**

This is a list of the changes:

1. All classes now have a namespace called ```HighRoller```.
2. The ```HighRoller``` class is now called ```HighRoller\ChartAbstract```, while changing the file name accordingly.
3. Removed the ```HighRoller``` from all the class names, while changing the file name accordingly. For example:
    *  Instead of ```HighRollerAreaChart```, the class is now ```HighRoller\AreaChart```.
4. The same is done for all the classes that are inside the now called ```ChartAbstract.php``` file.
5. Removed the closing PHP tag ```?>``` from the end of the class files.
6. There was a missing word (use) in the files license.
7. Fixed the example in the README, to use the new class names.
8. The ```autoload_classmap.php``` now returns an empty array since the classes will now get auto-loaded since they are using namespaces.

*There are other changes that still needs to be done though. Such as, each class should be its own file, tabs should be replaced by 4 spaces, etc.*