not allow to easily get the rank), fix a bug (which could have been
triggered by matrices having coefficients of very different
magnitudes).
Part: add an assert to prevent hard to find bugs
Swap: update comments
Note: in fact, inverse() always uses partial pivoting because the algo
currently used doesn't make sense with complete pivoting. No num
stability issue so far even with size 200x200. If there is any problem
we can of course reimplement inverse on top of LU.
pivoting for better numerical stability. For now the only application is
determinant.
* New determinant unit-test.
* Disable most of Swap.h for now as it makes LU fail (mysterious).
Anyway Swap needs a big overhaul as proposed on IRC.
* Remnants of old class Inverse removed.
* Some warnings fixed.
