Blender Git Loki

Armature Edit Mode: improve box/lasso select

Mostly rewrite logic which now matches (de)select picking,
share between both operators.

- Support all selection operations (eSelectOp), fixes T59255.

- Add function that selects using 'BONESEL_*' flags & eSelectOp.
This avoids lasso & box select having to handle selection flushing.

- Fix strange behavior with lasso where selecting a bone in a chain
would only select the tip (from 2.7x).