Release site with SHAPE set to uninstantiated box object

[jczech]

When you create a meta object with a child box object (or polygon object) and attempt to release within that object without first instantiating it, then an error is generated. Here is an example MDL:

ITERATIONS = 1000
TIME_STEP = 1e-6

DEFINE_MOLECULES{
  A {DIFFUSION_CONSTANT_3D = 1e-05}
}

boxy BOX {
  CORNERS = [-0.5, -0.5, -0.5],[0.5, 0.5, 0.5]
}

meta_box OBJECT {
  box1 OBJECT boxy{}
}

INSTANTIATE Scene OBJECT
{
  rel_A11 RELEASE_SITE
  {
    SHAPE = meta_box.box1
    MOLECULE = A
    NUMBER_TO_RELEASE = 5
  }
}

This will generate the following error:

****************
INTERNAL ERROR at ../src/wall_util.c:973 [is_manifold]: Region 'meta_box.box1,ALL'     has NULL wall array!
MCell has detected an internal program error.
Please report this error to the MCell developers at <mcell@salk.edu>.
****************

[haskelladdict]

Fixed with 5b3821edcf28c4b9a416f453d25e6a9af0777bd3.