Fix T38411: Free keyframe handles do not snap to frames when duplicating
Fix T38427: Sculpt mode dimension changes don't Undo
Fix cycles crash with float image textures on CPU without AVX support.

The AVX kernel functions for reading image textures could be get used from non-AVX
kernels. These are C++ class methods and need to be marked for inlining, all other
functions are static so they don't leak into other kernels.
Deb-like distro may use either jack or jack2, add support for this.
Cleanup: remove completely all-static option, just too complex to support in modern linuxes!
Correct help: -b/--background does not take a file argument

The documentation for the -b/--background option incorrectly states that it
takes a <file>, however it can run also without a file with e.g. a script.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D250
Fix missing $BLENDER_USER_DATAFILES in command line help text.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D249
SCons: cleaner determination of 32-bit/64-bit builds

Try not to be x86-centric, remove unneeded blenderdeps variable.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D240
SCons: code cleanup, shorter way to determine makesrna output directory.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D237
Correct 3d text editing update logic

- editmode operations were converting text->nurbs twice.
- cursor and selection operations were re-tessellating text every time.
Scanfill: minor optimization, comment unused code, avoid vert loop
Scanfill: optimize filling curves, text, masks - skip calculating holes

Support for tagging polygon numbers when adding scanfill data,
saves having to calculate connectivity afterwards (which can take approx half overall scanfill time for complex curves).
Code cleanup: remove scdata from ScanFillContext
Cycles: bvh_cardinal_curve_intersect intro SSE optimization

Gives 5% speedup for koro_final.blend, 10-15% for hair.blend

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D225
Attempt to fix OSL build error on Linux with latest OSL master.
BGE: Fixing memory corruption/double free when duplicating (e.g., addObject) LibLoaded lights.