Serial port listener: implemented data synchronization.

This class is now able to receive synchronized frames and sends
signals for each received frame.
The program now initializes a SerialPortListener instance.

-MainWindow:
    Added a SerialPortListener instance in the constructor.
    This instance is connected to the status tab port selector
    through the new 'setSerialPortListener' method of the StatusTab
    class.

-StatusTab:
    Defined and implemented the 'setSerialPortListener' method that
    connects the port selector text selection signal and the port selection
    slot of the SerialPortListener instance.
Fixed the serial port listener thread start.

-SerialPortListener:
    Fixed an issue where QThread::run was called instead of QThread::start.
    The thread was never started by the application.

-MainWindow:
    Connected the 'newStatus' signal from the serial port listener
    to the 'refresh' slot of the status tab.