[Bf-taskforce25] Blender spring cleaning

[bassam]

+1 on slow parent.
It's not that the feature isn't neat (it is!) but it comes with gotchas,
once you try to use it seriously, you get into trouble. I think it
should be removed unless it is replaced with something that is actually
safe to use- for instance, using bullet for fast physics in blender (not
just the ge)- in the time being, it's not a big loss to kill it now.