Blender Git Loki

Merge branch 'master' into blender2.8

PyAPI: add undo redo handlers

Useful so Python can clean up before/after undo steps.

Fix T55945: Outliner crash

crashed when using filtering and no item was found ('Blender File' mode)

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D3535

Fix T55949: increase color management exposure hard range.

Keymap: add 3D view snap popup

The key was available for other spaces,
removed because it conflicted with changes
which have since been reverted.

Keymap: add utility function for panel popups

Merge branch 'master' into blender2.8

Cleanup: header guards

Cleanup: style, duplicate header

Merge branch 'master' into blender2.8

Cleanup: pep8, cycles

Minor cleanup to last commit

No need to make attr-lists with the current layout logic.

UI: Group geometry in object visibility popover

Makes it easy to quickly hide all non-geometry.

Keymap: Modifiers to control mesh elem switching

Shift/Ctrl control extend/expand when number keys are used
to switch modes.

UI: minor edits to overlay popover

- Rename "Viewport Info" to "Text Info".
Name was too vague, nearly everything is information,
this currently only controls overlay text.

- Swap text-info & 3D-cursor, making 3D-cursor less prominent.

UI: 4-state icon for view visibility popover

This is a quick way to see if some of the object types in the
scene are hidden or unselected.

Icon design may change.

Merge branch 'master' into blender2.8

Icons: support setting blender, inkscape commands

Merge branch 'master' into blender2.8

Fix PyRNA class registration w/ Python 3.7

In Python3.7 this now raises an error.