Sandia National Laboratories recently changed management from the
Sandia Corporation to the National Technology & Engineering Solutions
of Sandia, LLC (NTESS). The copyright statements need to be updated
accordingly.
This is a fancy array handle that can group entries in another array by
arbitrary amounts. This allows us to implement input and output arrays
with a different sized Vec for each instance. This is necessary for
generating new topologies with cells of different types.
