message: Made DDI unit test more general
  use arbitrary not normalized bravais vectors
diff: @@ -63,8 +63,10 @@ n_interaction_pairs 0
  ### Lattice constant for basis and translations
  lattice_constant 2.77
  -### The bravais lattice type
  -bravais_lattice hex2d
  +bravais_vectors
  + 3 0 -1
  + 0 1 0
  +0.3 -2 1
  ### Number of basis cells along principal
  ### directions (a b c)
  