Add CaseInsensitivity to all of the completers.

Just one of the completers had Qt::CaseInsentitive set,
setting for all of them.

Fixes #400

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Setting dive as 'current' when restoring selection

Restoring the selection was not setting the selected dive as current, and
thus, breaking keyboard navigation.

Fixes #402

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>