parses a literal agent or agentset.
parses a literal agent or agentset. It recognizes a number of forms: {turtle 4} {patch 0 1} {breed-singular 2} {all-turtles} {all-patches} {observer} {breed some-breed} {turtles 1 2 3 4 5} {patches [1 2] [3 4] [5 6]} {links [0 1] [1 2]} To parse the turtle and patch forms, it uses parseLiteralAgent().