PENDING

* In logviewer.py, there are comments referencing activities (copy/pasted code)

* Icons to "show sources" and "show log" buttons.

* In the treeviews, sort first the directories and next the files.

* File operations (add file, add dir, delete file, delete dir) are using file choser.
  want implement these operations here? Now are commented.

* The clone capability is in sugar src/jarabe/view/customizebundle.py
  Probably should be moved to sugar-toolkit.

* Change the background (maybe grey) in the log files to show they are read only.

* Add gtk3 new activity template