Blender Git Loki

UI: add 3D view check for grease pencil tool

RNA: add space_type to tool

Adapted multisample functions.

UI: correct grease pencil placement text

Keymap: use Q key for quick menu in gpencil mode

Note, the keys for changing line display are now more obscure
(Shift-Q, Shift-Alt-Q), and might be changed.

Merge remote-tracking branch 'remotes/origin/blender2.8' into soc-2018-npr

# Conflicts:
# release/scripts/addons
# release/scripts/addons_contrib
# release/scripts/startup/bl_ui/properties_scene.py
# source/blender/draw/CMakeLists.txt
# source/blender/editors/space_outliner/outliner_draw.c

Merge branch 'master' into blender2.8

Cleanup: declare vars or make static

Merge branch 'master' into blender2.8

Move 'View3D.flag3' options into 'gp_flag'.

fixes for motion blur support

- added missing velocity interpolation. vertvel vector now pulls data
from interpolated vel grid (needed especially when using different
solver sizes)
- added missing cleanup calls on the python end (i.e. delete new python
motion blur objects too)

DNA: remove View3D.flag3

Having 'flag, flag2, flag3' is getting out of hand especially
when we support increasing the size of types.

Make flag2 into an int.

Note, this looses the 'show world' option,
but it's not such an important setting.

Fix T56181: Annotations hide proportionnal editing UI buttons

KnifeTool: Use GPUBatch API instead of IMM to fix buffer overflow issue

This also include a small optimisation (remove of a double loop and half of
the memory allocation for hit points)

This should fix T55946 Crash using knife tool on mesh with large number of
vertices.

Tried with a 500K vert suzanne and it seems fine.

Revert "Gitignore: Ignore diffs in all subdirs"

This is an issue for some file in the extern dir

This reverts commit d940a081a9f1f4106a5d2d155682695b0a6b0cb6.

Gitignore: Ignore diffs in all subdirs

Fix crash when rendering viewport within another area

This also Fix T55574 Crash on sequencer preview

GPUFrameBuffer: Put active framebuffer in GPUContext

instead of being ThreadLocal and leading to incorrect usage.

We still enforce no framebuffer when changing context. We can lift this
restriction later.

GPU: Replace malloc/calloc/realloc/free with MEM_* counterpart

Fix set_pixel overflow in fill brush

The value of the index was above the size of image

Fix: Motion Paths were still visible after clearing them

After clearing motion paths from objects, those objects needed to be
tagged for copy on write so that the copied data (i.e. viewport)
recieve the changes (i.e. removed paths)

Reported by Hjalti