upgrade bld_prep.sh debian libpng, add rectify timeline audio pref, rework maskgui layout yet again, igors icons, indexfile size in kb, mask_scale toggle imgs
add focus centroid to masking, mod mask reset/mode btns, add sticky to mask fade, rework mask gui layout
modify clr btn 16 plugins, add regdmp for sigtraps, rework mask_engine, mask rotate,scale,names,modes