Blender Git Loki

Merge branch 'asset-uuid' into asset-engine

Conflicts:
source/blender/blenkernel/BKE_asset_engine.h
source/blender/blenkernel/intern/asset_engine.c
source/blender/blenloader/BLO_readfile.h
source/blender/makesdna/DNA_ID.h
source/blender/makesdna/DNA_space_types.h
source/blender/makesrna/RNA_access.h
source/blender/makesrna/intern/rna_ID.c
source/blender/makesrna/intern/rna_asset.c