/// <summary>
 /// Unloads a unit from the host
 /// </summary>
 /// <param name="unit">Unit to unload</param>
 public void UnloadUnit( IUnit unit )
 {
     Arguments.CheckNotNull( unit, "unit" );
     Log.Info( "Unloading unit " + unit );
     unit.Shutdown( m_Environment );
     m_Units.Remove( unit );
 }