Wrap and log exceptions thrown when attempting to write to a serial port.
Icons for the power controls.
Factor out a "screen with back button" so that this can be made consistent across all screens. Currently only used by ProjectorScreensControl.
Convert system power screen to use common back button layout.
Blinds use common back-button layout.
Advanced menu uses common back button layout.
Log viewer also uses common back button.
Fix test by using findButton rather than trying to access members.
Advanced camera controls get the back-button treatment.
Push call to controller.getLog() into LogViewer itself.
Strip exceptions from the log that gets sent over the wire to the client, and replace them with a warning (that doesn't show up in the actual server log).
Fix up test to also use a mock MainWindow.