made gamma operator symmetric
made gamma operator symmetric

e3reiter/feltor,mwiesenberger/feltor,rkube/feltor,e3reiter/feltor,mwiesenberger/feltor,feltor-dev/feltor,rkube/feltor,feltor-dev/feltor,feltor-dev/feltor,rkube/feltor,mwiesenberger/feltor,feltor-dev/feltor,rkube/feltor,e3reiter/feltor,mwiesenberger/feltor,e3reiter/feltor,rkube/feltor,e3reiter/feltor