We need to call MainWindow::populateTable() when an SQL script was
executed during startup to make sure the latest data is shown. There is
however no need to do so when no SQL script was specified.
Support some additional command line options for opening and running SQL
scripts directly.
Don't just take the first argument as a SQLite database to open as it
could be a command line option - Qt and X11 have some default ones.
Remove two global variables storing the application short name which is
the same as the organisation name and the application icon which is only
used in one place.
Set the encoding used by Qt to UTF8. This fixes the wrong appearance of
special characters caused by SQLite using UTF8 and the application
ISO-8859 or whatever.