fix display elements order

selectAndSuggested method in store getter, is callable in all components,
and make union of two arrays: suggested and selected

* we need to have selected in last position (required for isChecked method to work well)
* but we want to display selected in first position (for better ux)

then, we use double inversion to obtain good behaviour

src/Bundle/ChillPersonBundle/Resources/public/vuejs/AccompanyingCourse/store/index.js

@@ -29,8 +29,8 @@ let getDataPromise = getAccompanyingCourse(id)
                      ).values()
                ];
                let union = [...new Set([
-                  ...state.add_persons.selected, 
-                  ...state.add_persons.suggested,
+                  ...state.add_persons.suggested.slice().reverse(),
+                  ...state.add_persons.selected.slice().reverse(), 
                ])];
                return uniqBy(union, k => k.id);
             }