Sat Jun 07 13:02:21 2008  Jiri (George) Lebl <jirka@5z.com>

	* src/matop.c, src/funclib.c, src/eval.c: Add a new flag to not do
	  backsubstitution in gauss if we are interested in nullspace and
	  the matrix is nonsingular
	
	* src/matop.c: fix the return value of gauss.  Singular means
	  nonempty nullspace, i.e. maximal row rank.  This also fixes
	  SolveLinearSystem which didn't work according to specs, i.e. it is
	  supposed to return null when solution is nonunique.

	* src/geniustests.txt: add more tests


svn path=/trunk/; revision=665