Blender Git Loki

Implement directional cluster based impulse pruning

Cycles Denoising: Cleanup by renaming a variable

Mesh batch caches should not be stored in file

Properties Editor: Collection context

Collections Editor: populate header with operators

SceneCollection.objects.active_index (for user interface)

Collection related operators barebones

Those are the operators for the collections editor, and the collection property panel

RNA: collection override

bpy.context.layer_collection

Fixed unfreed memory

Fix crash on read file

Fixed Pointer problem. Now materials are working.

Added scene.active_engine_settings

Collection Editor based on patch by Julian Eisel

This is extracted from the layer-manager branch. With the following
changes:

* Renamed references of layer manager to collections manager
* I didn't include the editors/space_collections/ draw and util files.

I still need to bring the drawing code here, so we see something.

Layers: allow anonymous collection, and set active collection when linking it

Fixed Engine name length

Fix read/writefile.c

Optimization: Use inertial solve for pre-collision

Instead of doing a full implicit pre-collision solve, do a simple
inertial solve (avance using velocities from previous step), this saves
time by doing one less solve per step, and also improves resting
stability by eliminating the influence of external forces disturbing the
mesh in contacting areas.

This improves general cloth performance by about 30-40% in relation to
the new cloth code, and improves performance by about 3 times in
relation to the original cloth code. This also makes collisions more
reliable by removing the need for positional interpolation, and thus
decreases the number of subframes required for a successful solve.

Changes to DNA/RNA. Follow same layout as sensors.

Merge branch 'blender2.8' into transform-manipulators