exports: create new aggregator tests + minor corrections in aggregators

src/Bundle/ChillActivityBundle/Export/Aggregator/ACPAggregators/DateAggregator.php

@@ -50,18 +50,15 @@ class DateAggregator implements AggregatorInterface
         switch ($data['frequency']) {
             case 'month':
                 $fmt = 'MM';
-
-break;
+                break;
 
             case 'week':
                 $fmt = 'IW';
-
-break;
+                break;
 
             case 'year':
                 $fmt = 'YYYY'; $order = 'DESC';
-
-break; // order DESC does not works !
+                break; // order DESC does not works !
 
             default:
                 throw new RuntimeException(sprintf("The frequency data '%s' is invalid.", $data['frequency']));