Py API: Vector.slerp(). also added interp_v3_v3v3_slerp(_safe) functions
Tweak slerp assert to be less picky
Add normal option to ED_transverts
Add Simple randomize vertex tool

D432 from Walid Shouman with normal & uniform options added.
Fix bug in image texture UI: "Use Alpha" checkbox doesn't appear if file format is BMP.
Maksing: fix issue when it's not possible to drag right handle of aligned handles
Masking: fix for initialdeather point not being offset to the mouse position
Code cleanup: use false/true/bool for masking
Code cleanup: use bool instead of short in motrack
Code cleanup: use bool insted of int/short in MCE
Fix T39405: Make "amplitude" for elastic easing more intuitive to use

Previously, amplitude was more of an "absolute" value in the sense that whatever value
you set it to became a sort of "maximum bounce" height. However, it turns out that this
approach isn't so nice when dealing with large gaps between the values of two keyframes,
as the elastic easing equations expect that "amplitude > |change|" (where change is the
difference in values from key1 to key2).

Now, the "amplitude" value we pass to the easing functions are "|change| + amplitude".
This is easier to control, as now, as soon as you start changing that value, there are
immediately visible effects.
Code cleanup: fixes for function prototypes
Fix T39510, Fix T39523: camera motion blur not working correct after recent changes.
Sculpt/dyntopo: Make the omp threads configurable to overcome performance issues
- autodetect optimal default, which typically avoids HT threads
- can store setting in .blend per scene
- this does not touch general omp max threads, due i found other areas where the calculations are fitting for huge corecount
- Intel notes, some of the older generation processors with HyperThreading would not provide significant performance boost for FPU intensive applications. On those systems you might want to set OMP_NUM_THREADS = total number of cores (not total number of hardware theads).
Fix T39525: branched path + no lights + disabled use all lights option crash.
Code cleanup: use bool/true/false in movieclip.c
Didn't meant to commit debug-only-code in the previous commit!
Vector handles were hidden but were allowed to slide apparently
Code cleanup: pack BezTriple a little (though size remains same)
Code cleanup: use bool