Allow the backspace key to delete stuff

macrovision.js

@@ -4010,7 +4010,7 @@ document.addEventListener("DOMContentLoaded", () => {
     document.querySelector("#options-reset-pos-y").addEventListener("click", () => { config.y = 0; updateSizes(); });
 
     document.addEventListener("keydown", e => {
-        if (e.key == "Delete") {
+        if (e.key == "Delete" || e.key == "Backspace") {
             if (selected) {
                 removeEntity(selected);
                 selected = null;