[gnome-db] gnome-database-properties

[Vivien Malerba <vmalerba gmail com>]

I've started cleaning the Libgnomedb for unused objects and widgets,
and I was wondering why the gnome-database-properties does display the
list of tables, instead of just being able to test if the connection
is OK (as it used to do some time ago).

I think that the gnome-database-properties program should be kept to
the minimum which is managing the connections declarations and testing
if the connections can be opened.

If you have no problem with that, I'll simplify the code to only show
if the connection to a datasource is possible.

Vivien