Bugfix T42763: In GPencil Edit Strokes: Proportional edit mode hidden when there is no active object in scene
Re-enabling keymappings for straight line and poly drawing

These are no longer blocked by the pie hotkeys, so they shouldn't be a problem
Improved Collada Armature Import

Collada does not support Bone length. It has only Joints.
This patch tries to improve the necessary "guesswork" for
importing Rigs.

Differential Revision: https://developer.blender.org/D920
Fix: Changing Grease Pencil datablocks updates the view
Fix: Forgot to set fill colour when drawing 2D filled strokes
Fix: Volumetric strokes now draw correctly in the Image Editor

This needed a correction factor (currently hardcoded to be 1 / 1000)
as it seems that the image editor uses 1 unit as its MAXIMUM dimension
whereas everything else uses 1 unit = 1 pixel.
Fix: Strokes in image editor can finally be drawn using "fancy" 2D stroke tesslation

Inspired by the previous commit, I've finally found a way to fix a long standing
limitation/bug which meant that Grease Pencil strokes in the Image Editor could
not be drawn using the fancy stroke tesselation code, and were instead done using
the plain old OpenGL strokes instead.
UI: auto-run error could push buttons off the visible header
CMake: fix for MSVC, installing Python
Cleanup: warnings
CMake: fix for msvc (take2)
Fix T42588: Absolute paths not cleaned on win32

Making paths absolute would leave in "\..\" part on windows.
Dim down default (no) material for cycles so it matches default material
in blender internal
CMake: Warning re: editing windows/py extraction
Cleanup: hopefully last int->bool one in this area!
Cleanup: more int->bool.
Python: add 'render_write' callback

This is useful for addons which intend to write data next to the rendered image/movie,
but not for preview renders.
Fix for potential bug in paint brush RNA updates, was casting to wrong
DNA type.

The update function is for the Paint struct, containing a Brush pointer
property, not Brush itself. Probably went fine so far because was only
used for a notifier pointer, but still ...
Collada Importer: Separated finding bone chains and fixing leaf bone orientations into 2 functions and added a separated import option
UI messages: Minor typo fix.