Bugfix T41077: Dope sheet's column select (alt + click) gets ignored with NLA Strips

NLA mapping corrections were being applied twice, causing column select to fail
Bugfix T41042: Irrelevant Bezier handles still affect Graph Editor Show All

The "Show All" and "Show Selected" operators in the Graph Editor was taking into
account all handles on keyframes, even when some of those would be invalid and/or
set to nonsense values (e.g. for any interpolation mode other than "Bezier")
Early out from gaussian blur if both sizes are zero
Sequencer: Fix wrong blur result when one of the sizes is zero
Update buildbot config to latest actual version
Correction to 7c7b730, multiplication order was flipped

That's really annoying that multiplication order is flipped
comparing mat3 and mat4 cases, but for the purposes of not
breaking all the branches which might use this stuff we'd
better keep order consistent with old version for now.

Suggestion here would be to make order consistent but rename
this functions to mult_* to make compilation fail instead
of failing and using wrong order silently.
Cleanup
bmesh py api: face_split_edgenet missed NULL check
Math Lib: Add isect_point_tri_v3

Add to Python via mathutils.geometry
Optimisation to rgb <-> hsv/l conversion

Basically avoid redundant computations. Gives ~1-4% speedup in the compositor depending on the use case.

For more info see: http://lolengine.net/blog/2013/01/13/fast-rgb-to-hsv

Reviewers: psy-fi, sergey

Subscribers: campbellbarton

Differential Revision: https://developer.blender.org/D596
Math Lib: rename mul_serie_m3 to mul_m3_series & reorder args

Importantly, reversed mul_serie_m3 argument order (so it matches the m4 function)
GSOC 2013 paint

Yep, at last it's here!

There are a few minor issues remaining but development can go on in
master after discussion at blender institute.

For full list of features see:

http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.72/Painting

Thanks to Sergey and Campbell for the extensive review and to the
countless artists that have given their input and reported issues during
development.
Cleanup
Fix errors in hsv calculation from recent optimization patch.

Code was different from original here, result was apparent in color
picker wedge position.
Bugfix T41133: Audio: Speakers with animated pitch cause clicks in rendered animations, crashes or huge filesizes in rendered audio

Crash happened when the pitch value got <= 0, preventing this now.
Py/API: Improve intersect_line_line with parallel lines

Now comparing the distance between line-intersection points
to see how close lines are - doesn't fail in the parallel case.
Fix T41128: Box selection bug with armatures.

Calling `glLoadName()` was possible with '-1' value (65535 actually), in `draw_pose_bones()`...

Note I think bug exists since ages (at least, seems to be already present in 2008
when drawarmature.c was added in repo)!

Odd behavior reported (issue only affected objects once parented to the armature) was
due to ordering stuff, since only objects drawn *after* the armature were affected.
Fix T40432: Scaling to zero with manipulate center points works precisely on second time

Commented out the 'no zero' protection of scaling transforms for numinput.

Issue is, once an axis has null scale, you can't regrow it from transform code
(you have to directly edit the scale property). This is not ideal, but getting
good behavior in this case is hairy...

Yet, when using numinput, you type precise values, so if you want to set it to zero,
set it to zero. User is assumed responsible, we should avoid too much 'invisible magic'
when handling precise inputs. ;)

Note: an idea for possible future feature would be to have an 'absolute' mode for numinput
(allowing to type in real value, not factors).
Transform: edit to recent commit

Copying long comments about & `#if 0` is hint it could be defined in one place.
Fix T40839: Object Font Text Rendering Bug

The issue was caused by the wrong objects order for
convertblender.c. Dependency graph totally missed
handling of this situation.

Fixed now, but it's not that pretty, don't try this
at home obviously. But consider this to be good enough
for the current dependency graph.

Details are in the build_dag_object().