Discard attribute typed arrays for buffered geometries that are not modified after initial rendering (#9512)

* add setDiscardBuffer method to BufferGeometry

* added discard support to BufferAttribute

* add mechanism for discard of BufferAttribute TypedArrays

* use more elegant method for creating dummy typed array.

* fix typo

* Update BufferGeometry.js

fix brain fade

* rework to use callbacks (phase 1)

* rework part 2

* remove build file

* support setting onUploadCallback from Geometry

* remove repeated calculation from renderer

* remove now redundant getter

* remove geoemtry interface

* document discard mechanism.

* merge fixes

* restore return.this

* drop unneeded call()

* rename discard() method to disposeArray()