Improve the Own Scripts menu entry

[a.l.e]

It took a long time, but now we have a way to add the user's scripts to the Scripter menu entries:

https://bugs.scribus.net/view.php?id=15579

Now that it's in, I plan to do some further work and improve it.

Some ideas are:

Adding a "refresh" button in the preferences to rebuild the list of scripts
Create some sort of manifest to define the menu structure and the names of the scripts
Allow the user to add scripts in a new first section of the Scripter menu entry (without the sub menu)

Any other inputs?

[AdmFubar]

Shouldn't the "refresh" be a menu entry in in the scripts menu?
and for the menu entry in the list of scripts, a title entry in the script itself to define its name?