Error out if someone tries to use PetscNonlinearSolver with no jacobian or no residual function set.
Error out if someone tries to use PetscNonlinearSolver with no
jacobian or no residual function set.



git-svn-id: ffc1bc5b3feaf8644044862cc38c386ade156493@3313 434f946d-2f3d-0410-ba4c-cb9f52fb0dbf

certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh