Merge branch 'gooseberry' into hair_system

Conflicts:
source/blender/blenkernel/intern/rigidbody.c

Fix compilation error with SCons

The file wasn't being comiling by CMake, remove it from SCons compilation as well.
Not sure if the same is required in original branch, maybe it'll be redone anyway.

For now let's make it so gooseberry branch is compiling nicely on the buildbot.

Merge branch 'master' into gooseberry

Merge branch 'wiggly-widgets' into gooseberry

Cage actually now draws something, also change widget, will be modified
to control placement of backdrop.

Another fix for particle instance child lookups, was not subtracting
parent amount.

Fix for invalid particle pointer access in mixed particle/child loop.

Better update function for particle settings affecting nested cloth
modifier.

Fix for applying the bending randomness factor.

A stupid hack is needed here, changing the way the factor is applied to
angular bending springs. In cloth sim the bending factor of individual
springs is applied as a mix value between the bending stiffness and a
max value, but this max value isn't even used in hair sim so that
approach becomes useless.

Randomness factor for hair bending stiffness.

This helps to create some variation in a hair system, which can
otherwise become very uniform and boring. It's yet another confusing
setting in a system that should have been nodified, but only option for
now (broken windows ...)

Fix for particle instance initial frames.

These were not orthonormal and tended to flip with changing hair
direction, now use the particle hair matrix which is stable wrt. the
mesh surface.

Merge branch 'master' into wiggly-widgets

Fix T42639, editcurve flags not getting restored on undo.

Error here could be reproduced by tweaking curve properties such as
2d-3d or fill type and undoing.

Initialize the snaping aspect just once.

Merge branch 'master' into gooseberry

Merge branch 'wiggly-widgets' into gooseberry

Fix crash with widgetgroup

Merge branch 'wiggly-widgets' into gooseberry

Conflicts:
source/blender/editors/include/ED_view3d.h
source/blender/editors/space_view3d/view3d_draw.c
source/blender/editors/transform/transform_manipulator.c

lost instance of transform manipulator

Merge branch 'master' into wiggly-widgets