Added CLOSURE .

* SPECIAL CHECKPOINT:
CLOSURE feature added bring along way many changes to the Evaluator.
- Lookup / Extend / Push / Pop are now all inside the current Closure
frame level.
- New defined words are only appear in Closure frame.
- Lookup work on primitives first, then to local  ( Or vice versa
depend on performance test )
- Push / Pop is not very depend but there certainly are case when out of
closure scope they also lost their previous evaluated result , and
this's not very well change , indeed. Return Stack should be united
throughout Closure frame to maintain the relay effect.
- CLOSURE - Require LAZY to work absolute effect against special
keywords.