Added page scripts and styles

page-scripts/page-script.js

@@ -0,0 +1,13 @@
+var p = document.createElement("p");
+p.textContent = "This paragraph was added by a page script.";
+p.setAttribute("id", "page-script-para");
+document.body.appendChild(p);
+
+window.foo = "This global variable was added by a page script";
+
+window.confirm = function() {
+  alert("The page script has also redefined 'confirm'");
+}
+
+// add controls
+insertControls(document.getElementById("left-column"), "Page script controls");