Removed semi colons after variable_xx() and arg()

The automatic semi colon after an autocompleted `variable_get()` is usually unwanted. There were 7 functions I could find that had this semi colon. 3 of which are `db_xxx()` functions, which are rarely arguments in another construct, so they're find there.

Somewhat useful:

    db_delete('foo');

Hardly ever useful:

    variable_get('foo');

(`db_delete()` has an autocomplete bug btw: `db_delete('table', array()PDOException);`)