Fixed evaluation and optimization of inverse condition number in 2D

git-svn-id: https://geuz.org/svn/gmsh/trunk@19683 59c8cabf-10d6-4a28-b43f-3936b85956c4
git-svn-id: https://geuz.org/svn/gmsh/trunk@19684 59c8cabf-10d6-4a28-b43f-3936b85956c4