Remove default scaling of the system. The scaling doens't seem to help actual solutions. One example that fails in the flexural code. With large timesteps the solutions seems to blow up. One particular example is profilePresentation on the tdb_presentation_figures branch with k = 0.0005

A grid.boundaryIdentifier identifies a boundary of a grid.
For a Cartesian grid it is simply 's', 'n', 'w', 'e'.
For a multiblock grid it might be something like {1, 's'}.
For some other grid it will be up to the developer to chose
a good way to identify boundaries.