Merge branch 'blender2.8' into transform-manipulators

Conflicts:
intern/gawain/gawain/immediate.h
intern/gawain/src/immediate.c
source/blender/editors/physics/physics_ops.c
source/blender/editors/screen/glutil.c
source/blender/editors/space_view3d/space_view3d.c
source/blender/editors/space_view3d/view3d_draw.c
source/blender/editors/space_view3d/view3d_edit.c
source/blender/editors/space_view3d/view3d_ops.c
source/blender/editors/transform/transform_manipulator.c

Merge branch 'blender2.8' into transform-manipulators

Conflicts:
source/blender/editors/interface/resources.c
source/blender/editors/space_view3d/view3d_intern.h
source/blender/editors/transform/transform_manipulator.c
source/blender/gpu/CMakeLists.txt
source/blender/gpu/intern/gpu_shader.c

Merge branch 'blender2.8' into transform-manipulators

Merge branch 'blender2.8' into transform-manipulators

Merge branch 'blender2.8' into transform-manipulators

Conflicts:
source/blender/editors/space_view3d/view3d_edit.c
source/blender/editors/space_view3d/view3d_ops.c
source/blender/editors/transform/transform_manipulator.c

Merge branch 'blender2.8' into transform-manipulators

Merge branch 'blender2.8' into transform-manipulators

Conflicts:
source/blender/blenloader/intern/versioning_270.c
source/blender/editors/interface/resources.c
source/blender/editors/screen/glutil.c
source/blender/gpu/intern/gpu_shader.c

Fix out of bound array access

And other minor fixes.

Use axes colors from custom-manipulators branch

Don't draw helplines when using transform manipulators

Also removed unused transform flag.

Remove bad storage hacks of old transform manipulators

Got rid of Scene.twcent, Scene.twmin, Scene.twmax, RegionView3D.twmat, RegionView3D.twdrawflag, RegionView3D.tw_idot, TransInfo.mat, TransInfo.vec.
Also cleaned-up variable and define names.

Decided to completely remove the struct members without doing proper file conversion for non-runtime ones. That will cause minor compatibility breakage but that's okay for 2.8.

Remove old transform manipulators code

Merge branch 'blender2.8' into transform-manipulators

Conflicts:
source/blender/gpu/intern/gpu_shader.c

Rotation value indicator for rotation manipulators

Adds the arc thingy that displays the current delta rotation value while rotating.
It is a different implementation than the one of the custom-manipulators branch which was based on mouse coordinates and thus didn't work correctly with snapping and precision (shift) tweaking. This new implementation is based on object matrix and fixes these issues.

Commit only adds support for rotating objects, not yet for other elements (polygons, bones, GPencil points, etc)
Also some minor cleanup of course ;)

Make transform manipulators of multiple types work together nicely

Some cleanups/refactors for transform manipulators

Add missing file

Implement new resize manipulators

Use more modern OpenGL for dial manipulator drawing

Added a new shader for drawing with clipping plane.

Merge branch 'blender2.8' into transform-manipulators