- Tank emptying on start-up implemented, EmptyTimeSec parameter added to Balances

- added events Event.TimerBusy, Event.ValvesBusy, etc.
- fixed bug in SetValvesOp
- preparing a virtual bench drawing on the Process screen - partly done

TestBenchFramework/BenchControl/MettlerToledo/BalanceDev.cs

@@ -44,7 +44,8 @@ namespace TBF.BenchControl.MettlerToledo
 		public string Name { get { return balanceCfg.Name; } }
         public int BalanceNr { get { return balanceNr; } }
         public float Capacity { get { return balanceCfg.Capacity; } }
-		public IList<Entities.MeasurementCorrection> Corrections { get { return balanceCfg.Corrections; } }
+        public int EmptyTimeSec { get { return balanceCfg.EmptyTimeSec; } }
+        public IList<Entities.MeasurementCorrection> Corrections { get { return balanceCfg.Corrections; } }
 
 		/// <summary>The state of the mass measurement</summary>
 		public MsrmntState MsrmntState