When iterating a data file, loop back to the beginning rather than re…

…peat the last element

lib/runner/extensions/waterfall.command.js

@@ -51,13 +51,8 @@ extractSNR = function (executions, previous) {
  * @return {Any} - The data for the iteration
  */
 getIterationData = function (data, iteration) {
- // if iteration has a corresponding data element use that
- if (iteration < data.length) {
- return data[iteration];
- }
-
- // otherwise use the last data element
- return data[data.length - 1];
+ // if iteration has a corresponding data element use that, otherwise, start from the beginning again.
+ return data[iteration % data.length];
 };
 
 /**