Workaround for wizard radio buttons on Mac - needs testing on other platforms

The radio buttons and checkboxes on the Wizard are rendered very close together. It looks similar to this reported bug in Qt:
https://bugreports.qt-project.org/browse/QTBUG-14591?page=com.googlecode.jira-suite-utilities:transitions-summary-tabpanel

The suggested workaround is to set the Qt::WA_LayoutUsesWidgetRect attribute on all the affected widgets.

This needs testing on other platforms.