By removing the setText updates, OPMap CPU costs drop 8%.

### RFC: seeking feedback.

This is highly odd. I have tracked down a serious performance hit to the setText(). On OSX 10.8 I am able to consistently and repeatedly reduce processor load by 8% when removing the ```m_widget->labelUAVPos->setText(str)``` line.

This makes no sense to me, but is easy to demonstrate. The ```connect(m_statusUpdateTimer, SIGNAL(timeout()), this, SLOT(updateMousePos()))``` line is commented out because it also produces the same processor spike. To see this processor spike, in a normal GCS from next, simply go to the map widget and watch the processor load as you move the mouse cursor.

On Linux, the savings are 4-6%. @jan76 reported 5% on Windows.

This is with the default settings. I am completely puzzled about why this should happen. Thoughts?