SUP-2943, Add volatility to top-line SRM stats on Profile

-- Added volatility to the data of interest.
-- Fixed unit tests to validate the same

Author: vikasrohit

app/services/userStats.service.js

@@ -40,7 +40,8 @@
         {key: 'rank.rating', label: 'rating', postFunc: null},
         {key: 'rank.rank', label: 'rank', postFunc: null},
         {key: 'rank.percentile', label: 'percentile', postFunc: percentileFunc},
-        {key: 'challenges', label:'competitions', postFunc: null}
+        {key: 'challenges', label:'competitions', postFunc: null},
+        {key: 'rank.volatility', label: 'volatility', postFunc: null}
       ],
       'DATA_SCIENCE.MARATHON_MATCH': [
         {key: 'rank.rating', label: 'rating', postFunc: null},

app/services/userStats.service.spec.js

@@ -39,9 +39,9 @@ describe('User Stats Service', function() {
 
     it('should return stats for data-science: srms ', function() {
       var _data = UserStatsService.getIterableStats('DATA_SCIENCE', 'SRM', stats);
-      expect(_data).to.have.length(4);
-      expect(_.pluck(_data, 'label')).to.have.members(['rating', 'rank', 'percentile', 'competitions']);
-      expect(_.pluck(_data, 'val')).to.have.members(['799', '6,280', '26%', '10']);
+      expect(_data).to.have.length(5);
+      expect(_.pluck(_data, 'label')).to.have.members(['rating', 'rank', 'percentile', 'competitions', 'volatility']);
+      expect(_.pluck(_data, 'val')).to.have.members(['799', '6,280', '26%', '10', '473']);
     });