TableView: Fix rowAt function

Task-number: QTBUG-31160

Change-Id: Ife5837645636be1b2b2ee5cf9b0aa27ac04c2dc0
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Doc: Small fixes

Change-Id: I1ee810dfcd57fd9ff7ddf65c87208c8b457f755e
Reviewed-by: Nico Vertriest <nico.vertriest@digia.com>
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>