Ux improvements

Add the option to delete a command set.
Put back icons reference in config file.

To test the delete a command set option:

1. Run the app.
2. Go to the command sets window.
3. On the command set list, swipe to the left on the command set you want to delete.
4. A trash icon should be visible now.
5. Click the trash icon.
6. Command set should now be deleted and the list updated.