Value looper related fixes

Turned ValueLooper into abstract class and added abstract method
setupValueLooper(?)
Also made new class BlendModeValueLooper - which is a subclass of
ValueLooper<> and the BMVL implements the abstract setup method. This
way the initialization of the looper is done in this one place.
(partitioned).
in sun.pde - removed call to setupValueLooper() method
from setupValueLooper - actually removed the method for setting up the
looper and moved it to the BMVL.
Also the BMVL instance is inline created.  In future need to move this
variable to main tab.
valueLooper is not declared in main tab. no need for setupVL.pde tab
sealed into class functionality around image display

also modified main tab to call the modified calling to image class.
moved setLineStroke() from main tab to NoiseCircle
Renamed NoiseCircle into Nircle
Made main tab ONLY use NircleSystem to display circle.

I removed all references to individual Nircles(NoiseCircles) and relate
variables.
Now the main tab only operates the NircleSystem
NS creates (so far in default pos) nircles and draws them

INFU need to pass surface paramters, so that nircles can be produced in
different spots.