Address comments on 058b5a802f

Also address some from 67b1857e58 which got left out of the previous
commit

bpkg/__init__.py

@@ -340,7 +340,13 @@ class USERPREF_PT_packages(bpy.types.Panel):
         return (userpref.active_section == 'PACKAGES')
 
     def draw(self, context):
-        repo = context.user_preferences.addons[__package__].preferences['repo']
+        try:
+            repo = context.user_preferences.addons[__package__].preferences['repo']
+        except KeyError:
+            # HACK: 
+            # If no repositories are initialized, we should try to refresh them. If that doesn't work, display a message
+            repo = {'packages': []}
+
         layout = self.layout
 
         main = layout.row()