BMesh Walker: typecheck args for walker->begin()
BMesh Walker: rename BMW_SHELL -> BMW_VERT_SHELL
BMesh Walker: add face-shell walker
Fix T40324: Checker deselect fails for edge-rings
Checker Deselect: keep active item selected by default
Spelling fix
Fix T40325: Part II

Use same cursors for GRIP buttons as for window resize e.g.
Report to the console when custom ocio config is used
Optimization of keying clip operations

Gives around 20%-30% speedup by doing early exit from
kernel traversal cycle.
Fix T40320: wrong render layer visibility with cycles deformation motion blur.
Fix crash rendering linked scenes in compo

Simply linking scene (lib.blend) without compo into another one (compo.blend),
using it in a compositor and rendering it would crash.
Some operation allowed to set invalid active scene render layer

Forbid this now and do tricks in the versioning code to repair
corrupted files.

Thanks to Pablo, Caminandes and Koro for discovering this bug!
Cleanup: Comments and unused variables.
msvc 2008 platofrm suffix changed to be -vc9
Fix T40331: Incorrect display of path of editted data.
Revert "Cycles-Bake: fix T40322 Glitch in baking a mixed SSS shader"

This reverts commit 81b129d3b837e31c0d6d2a9d2a6e39d39e47c1ec.

This is not the correct fix yet. More details in T40322
Fix T40438: Pressing G key to move the camera quits Blender.
Freestyle: Partial fix for thinning strokes due to flipping stroke directions at TVertices.

A description of the problem is found in https://developer.blender.org/T36425#19 .

The cause of the issue was identified as roudning errors in Operators::createStroke() due
to insufficient numerical precision.  Precision promotion from float to double was done in
the return values of getPoint3D/2D methods in Interface0D and its subclasses in C++
(data members stored in the 0D classes have already been in double precision).
Fix Sequencer OpenGL render ignoring preview channel
Fix for curve having invalid active vertex after setting type

also allow passing NULL vertex to BKE_curve_nurb_vert_active_set