Blender Git Loki

Merge branch 'asset-experiments' into asset-engine

Conflicts:
source/blender/editors/space_file/filelist.c
source/blender/editors/space_file/filelist.h
source/blender/makesrna/intern/rna_internal.h

Notes:
* asset-experiments branch still needs some work (e.g. entires selection is to be reworked too),
but was more than time to do a first merge...
* This is raw merge, code is hence broken and needs more fixes to take into account new changes!