execute Python script option should provide visual feedback while waiting to start

```
The File > Execute Python script... option should provide some visual feedback
such as a pop-up dialog with spinning bar graph that says "running Python
script 'myscript.py'..." before the session is connected.
```

Original issue reported on code.google.com by `ahrenh...@gmail.com` on 11 Sep 2013 at 11:20

Start at the File > Execute Python script... action and trace how it waits before the session is connected. Done means showing a pop-up with a spinning bar graph and the message "running Python script 'myscript.py'..." before connection begins.

Written by the indexing model from the issue text.