with permission of the original author.
The Lemke implementation is not fully working yet:
1) we need to convert the lo-high LCP problem into a problem without the lo/high
2) we need to sort out the remaining instabilities, and report a failure if the max loopcount is reached etc.
We replaced the fmatvec library with our own LinearMath/btMatrixX.h, and STL std::vector with btAlignedObjectArray
Removed some warnings/potential issues: use fuzzyZero instead of isZero, and some warnings,
related to this issue 756
Apply patch for CMake config, see Issue 754 (Issue 753)
Fix a few issue with the MLCP solver: allow split impulse, and fix offset in friction dependencies
Added a PGS solver that uses the sparsity of the A matrix, just for testing (the equivalent sequential impulse solver is much faster, not having to allocate the big matrices)
