Remove commented code

Author: alex-kulakov

Orm/Xtensive.Orm/Orm/Rse/RecordSetHeader.cs

@@ -145,19 +145,15 @@ public RecordSetHeader Join(RecordSetHeader joined)
       var groups = new List<ColumnGroup>(columnGroupCount + joined.ColumnGroups.Count);
       groups.AddRange(ColumnGroups);
       foreach (var g in joined.ColumnGroups) {
-        //var keys = new List<int>(g.Keys.Count);
         var keys1 = new int[g.Keys.Count];
         var ai = 0;
         foreach (var i in g.Keys) {
           keys1[ai++] = columnCount + i;
-          //keys.Add(columnCount + i);
         }
-        //var columns = new List<int>(g.Columns.Count);
         var columns1 = new int[g.Columns.Count];
         ai = 0;
         foreach (var i in g.Columns) {
           columns1[ai++] = columnCount + i;
-          //columns.Add(columnCount + i);
         }
         groups.Add(new ColumnGroup(g.TypeInfoRef, keys1, columns1));
       }