Fix compilation issue with std::isinf
Finish memory_pool implementation in container.h
Use of matrices allocated in memory pool for intermediate results in
dense linear algebra operations in inmost_dense.h
Use of memory pool for matrices in inmost_autodiff.h
Change error reporting and return type in Invert, Solve,
CholeskyInvert, CholeskySolve, PseudoInvert, PseudoSolve
Add unit tests for linear algebra on dense matrices.
