Add OperationsPerSecondAttribute (#2468)

Author: DarkWanderer

src/BenchmarkDotNet/Attributes/Columns/OperationsPerSecondAttribute.cs

@@ -0,0 +1,10 @@
+using BenchmarkDotNet.Columns;
+using JetBrains.Annotations;
+
+namespace BenchmarkDotNet.Attributes
+{
+    public class OperationsPerSecondAttribute : ColumnConfigBaseAttribute
+    {
+        public OperationsPerSecondAttribute() : base(StatisticColumn.OperationsPerSecond) { }
+    }
+}