build: Crush all the PNGs

Refactored CM's opticharger to match with MoKee's build system,
will only optimise UNOFFICIAL, NIGHTLY and EXPERIMENTAL builds

Change-Id: I8f2948fad5711d2eadc376372cbec6e21e0ab509

Conflicts:
	core/Makefile

Conflicts:
	core/Makefile
Merge branch 'psoa_r2' of https://github.com/EuclideanROM/platform_build into psoa_r2