The stuff of “Star Wars” — and there is unfortunately no better way to adequately describe the Death Star-sized planet of stuff that has been created in response to “Star Wars” since 1977 — filled McCormick Place through Monday. Since many of you weren’t able to make it to Lucasfilm’s extravagant Star Wars Celebration there, I wanted tell you about some of that stuff, because there is so much of it, there should be an official metric for measuring the gross weight of “Star Wars”-inspired objects that exist.