Adds more readability to the class internals.

Changes:
  - creator (static) methods, and singleton methods (static) are always at the top of the class
  - Constructors, destructros, and init methods comes next
  - Then the instance methods for the class
  - Then the overriden methods
  - and finally the ivars

Also, overriden methos have the "override" context keyword
Merge pull request #3157 from ricardoquesada/override_love

closed 2407: Adds more readability to the class internals.