communication to the metamoodel of the Gmsh batch and loop status; OL preprocessors returns the /changed/ status of the client; /changed/ flag of all parameters set to false after a /compute/; param attributes updated (not replaced) by a parameter redefinition; + some clean up 

git-svn-id: https://geuz.org/svn/gmsh/trunk@18371 59c8cabf-10d6-4a28-b43f-3936b85956c4
Fix illegal corruption in Basis::getDerivative for 0 and 1 forms

git-svn-id: https://geuz.org/svn/gmsh/trunk@18372 59c8cabf-10d6-4a28-b43f-3936b85956c4