1) Add fast branchless SIMD support for constraint solver (Windows only until we get other contributions).
See resolveSingleConstraintRowGenericSIMD in Bullet/src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.cpp
resolveSingleConstraintRowGenericSIMD can be used for all constraints, including contact, point 2 point, hinge, generic etc.
2) During this refactoring, all constraints support the obsolete 'solveConstraintObsolete' while we add 'getInfo1' and 'getInfo2' support.
This interface is almost identical interface to Open Dynamics Engine, to make it easier to port Dantzig LCP solver.
3) Some minor refactoring to reduce huge constructor overhead in math classes.
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