/****
 *
 * Class RSLToUML contains functions to translate an RSL spec into a UML
 * diagram, per the following conventions:
 *
 *     (1) The top-level objects of the components hierarchy are identified
 *         as those objects that are a component of no other object and inherit
 *         from no other object.  If no such objects exist, the top-level
 *         objects are identified as those that are a component of the fewest
 *         other objects.  Once identified, the top-level objects are displayed
 *         as the top-most (geometrically leftmost) diagram nodes.
 *
 *     (2) The top-to-bottom order of the top-level nodes is from largest to
 *	   smallest in size, where size is measured in terms of the transitive
 *         number of components for each top-level object.  The order of
 *         objects of the same size is alphabetic by name.
 *
 *     (3) For an object that is inherited from, its inheritees are shown
 *         immediately to the right, extending downward, connected with a
 *         hollow left-pointing arrow.  The top-to-bottom order of inheritees
 *         is alphabetic by name.
 *
 *     (4) For each object that has components, the atomic components are shown
 *         immediately below the parent object name in the second part of a
 *         three-part box, in declared order.  Non-atomic components are shown
 *         immediately to the right, extending downward in declared order,
 *         connected with a hollow diamond symbol.
 *
 *     (5) Union components are denoted with a vertical bar when atomic, or
 *         with a hollow diamond with the word "or" as a superscript when
 *         non-atomic.
 *
 *     (6) Anonymous non-atomic components are shown with the name
 *         "Anonymous".
 *
 *     (7) Operations are shown in the third part of a three-part box for each
 *         object that has operations.  The operations are identified as those
 *         (and only those) explicitely listed in the operations attribute, if
 *         the operations attribute is defined.  If the operations attribute is
 *         not defined, the object's operations are identified as those in
 *         which the object appears at least once in the signature.  The
 *         top-to-bottom order of identified (as opposed to declared)
 *         operations is in three groups, alphabetic within each group: (1) obj
 *         is both input and output, (2) object is output only, (3) object is
 *         input only.
 */