Update bullet source to 2.82 rev2704
More bullet source updates (rev2704)
Fix build + add callbacks + add btSimplexSolverInterface
Swig generated files
Include original files to reference custom patch
Re-apply: fixed btScalar to not use SSE on iOS simulator
Update VS project
Merge pull request #864 from xoppa/bullet

Bullet: update to 2.82 rev 2704