Skip rendering attachments at joint positions

Since we aren't yet handling the joint location correctly, attachments to
joints show up in weird positions (such as weapon appearing in front of an AI's
feet). For now we just skip rendering attachments altogether if they have a
"joint" parameter set.

radiantcore/entity/EntityNode.cpp

@@ -122,6 +122,11 @@ void EntityNode::createAttachedEntities()
     _spawnArgs.forEachAttachment(
         [this](const Entity::Attachment& a)
         {
+            // Since we can't yet handle joint positions, ignore this attachment
+            // if it is attached to a joint
+            if (!a.joint.empty())
+                return;
+
             // Check this is a valid entity class
             auto cls = GlobalEntityClassManager().findClass(a.eclass);
             if (!cls)