- 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/GenericDevices/IBalance.cs

@@ -10,7 +10,7 @@ namespace TBF.BenchControl.GenericDevices
 	public interface IBalance : IDevice, IComponent
 	{
         /// <summary>
-        /// Camera number: 0-based index required for communication with the Elde component
+        /// Balance number: 0-based index required for communication with the Elde component
         /// </summary>
         int BalanceNr { get; }
 
@@ -24,6 +24,12 @@ namespace TBF.BenchControl.GenericDevices
         /// </summary>
         bool IsEmpty(float mass);
 
+        /// <summary>
+        /// Time in seconds to empty the tank completely when it is full
+        /// </summary>
+        int EmptyTimeSec { get; }
+
+
         /// <summary>
 		/// Measurement correction table
 		/// </summary>