0027691: Remove dchrono from all test cases and move its to perf group

Remove performance comparing with hardcoded value.
Test cases for performance of some commands were moved to perf group.

Updated documentation.

src/OSD/OSD_Chronometer.cxx

@@ -199,6 +199,17 @@ void OSD_Chronometer::Reset ()
   Cumul_user = Cumul_sys = 0.;
 }
 
+
+//=======================================================================
+//function : Restart
+//purpose  :
+//=======================================================================
+void OSD_Chronometer::Restart ()
+{
+  Stopped = Standard_True;
+  Start();
+}
+
 //=======================================================================
 //function : Stop
 //purpose  :

src/OSD/OSD_Chronometer.hxx

@@ -54,7 +54,10 @@ public:
 
   //! Stops and Reinitializes the Chronometer.
   Standard_EXPORT virtual void Reset();
-  
+
+  //! Restarts the Chronometer.
+  Standard_EXPORT virtual void Restart();
+
   //! Stops the Chronometer.
   Standard_EXPORT virtual void Stop();
   

src/OSD/OSD_Timer.cxx

@@ -125,6 +125,18 @@ void OSD_Timer::Reset ()
   OSD_Chronometer::Reset();
 }
 
+//=======================================================================
+//function : Restart
+//purpose  :
+//=======================================================================
+
+void OSD_Timer::Restart ()
+{
+  TimeStart = GetWallClockTime();
+  TimeCumul = 0.;
+  OSD_Chronometer::Restart();
+}
+
 //=======================================================================
 //function : Show
 //purpose  : 

src/OSD/OSD_Timer.hxx

@@ -52,7 +52,10 @@ public:
 
   //! Stops and reinitializes the timer with zero elapsed time.
   Standard_EXPORT virtual void Reset() Standard_OVERRIDE;
-  
+
+  //! Restarts the Timer.
+  Standard_EXPORT virtual void Restart() Standard_OVERRIDE;
+
   //! Shows both the elapsed time and CPU time on the standard output
   //! stream <cout>.The chronometer can be running (Lap Time) or
   //! stopped.