Fix #46, gauss_jordan elimination
Fix #46, gauss_jordan elimination

While it has mostly been fixed, there is still some error introduced by
the fact that IEEE 754 floating point values are used in the
calculation. Will look for a way to fix this in the future.

JeebsM/jstat,JeebsM/jstat,NorthDecoder/jstat,NorthDecoder/jstat,smarden1/jstat,cmpolis/jstat,jstat/jstat,smarden1/jstat,ggonzale/jstat,akrawitz/jstat,akrawitz/jstat,jamescgibson/jstat,jstat/jstat,ggonzale/jstat