QtIFW

Fix for QTIFW-103 and update on QTIFW-75.

We missed a connect, thus the label on the right got only updated
in case we switched the current node as well. Also hide 0 size infos.

Change-Id: I7aa5b689ed9928fc4918b6e9cf651d14183e25a8
Reviewed-by: Alexander Lenhardt <alexander.lenhardt@nokia.com>
Reviewed-by: Iikka Eklund <iikka.eklund@digia.com>
Reviewed-by: Niels Weber <niels.2.weber@nokia.com>