Information in the progress window (example: rescan) is displayed capped to fixed size instead of contents.

<img width="209" alt="screenshot 2018-12-21 at 14 58 20" src="https://user-images.githubusercontent.com/26601261/50345943-0bbd4300-0531-11e9-9c6c-e277ac69eb0c.png">

{
    onDisplayUnitsClicked(event->pos());
}
void UnitDisplayStatusBarControl::createContextMenu()
{
    menu = new QMenu(this);
    for (const BitcoinUnits::Unit u : BitcoinUnits::availableUnits())
    {
        QAction *menuAction = new QAction(QString(BitcoinUnits::longName(u)), this);
        menuAction->setData(QVariant(u));
        menu->addAction(menuAction);
    }
    connect(menu, &QMenu::triggered, this, &UnitDisplayStatusBarControl::onMenuSelection);
}
void UnitDisplayStatusBarControl::setOptionsModel(OptionsModel *_optionsModel)