CREASS ( type, assemb, ifail )
==============================

  Create assembly.

Receives:
  KI_cod_tyas              *type           --- type of assembly to create

Returns:
  KI_tag_assembly          *assemb         --- new assembly
  KI_cod_error             *ifail          --- failure indicator


Description:
  CREASS creates a new assembly and attaches it to the world. The new assembly
  has no instances and is not instanced. The box of the assembly will be unset.
  The state of the assembly will be new (ENSTNW) and it will have no key.

  'type' must be a token of the form TYASxx. At present the only acceptable type
  of assembly is collective (TYASCL).