QtIFW

store commits locally in settings

that way a user does not need to enter all repositories again. Only
valid entries will be stored, so the lists should not become overblown
in a regular situation.

Change-Id: I694d564dd0f0f1e8ea54f083aab586800e74ea34
Reviewed-on: http://codereview.qt-project.org/4954
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Tim Jenssen <tim.jenssen@nokia.com>