Pass.setSize - make resizing of passes automatic through EffectComposer.setSize (#8925)

* add Pass.setSize() and have it called automatically by EffectComposer.setSize()

* fix minor bugs in EffectComposer.setSize routine.

* fix buggy prototype usage in Pass derived classes.

* fix buggy prototype usage in Pass derived classes.

* remove constructors as suggested by @mrdoob

* fix MaskPass's prototype.

* init pass side when added to compositor.

* tabify EffectComposer.js

* simplify for loop.