Refactor for ControllerGroup + synchronized

[GoToLoop]

• I wasn't expecting almost 1000 lines of code, but I've taken the challenge anyways.
• Placed localized synchronized () not only for those 2 Vector containers from controllers field, but also for the 2 ArrayList in ControllerGroup class.
• Mostly for all sections doing iteration on them, but also when their size() changes.
• Prepended @Override for all inherited methods in ControllerGroup class.
• Prepended final for all fields which didn't seem they would be re-assigned.
• Lotsa further cleanups I can't remember I did. :P

[sojamo]

Hi @GoToLoop thank you for looking into this however I wont include your suggestions or fix the issue after I have reviewed and evaluated the concurrency issues. I hope you don't mind I close your pull requests.