Delete the getURLsSbeOrRelative(url) function

This function was only used for tools.xml, and didnt even do its job...
As of this writing, it simply prepended the `baseURL` variable, which is
determined by the Snap! server, not s.b.e.

If we want to have s.b.e as a permanent fallback source we should re-implement
this in a way that is used for all Snap! media.

gui.js

@@ -2559,9 +2559,7 @@ IDE_Morph.prototype.projectMenu = function () {
         'Import tools',
         function () {
             myself.droppedText(
-                myself.getURLsbeOrRelative(
-                    'tools.xml'
-                ),
+                myself.getURL('tools.xml'),
                 'tools'
             );
         },
@@ -4483,22 +4481,6 @@ IDE_Morph.prototype.getURL = function (url) {
     }
 };
 
-IDE_Morph.prototype.getURLsbeOrRelative = function (url) {
-    var request = new XMLHttpRequest(),
-        myself = this;
-    try {
-        request.open('GET', baseURL + url, false);
-        request.send();
-        if (request.status === 200) {
-            return request.responseText;
-        }
-        return myself.getURL(url);
-    } catch (err) {
-        myself.showMessage(err);
-        return;
-    }
-};
-
 // IDE_Morph user dialog shortcuts
 
 IDE_Morph.prototype.showMessage = function (message, secs) {