for each selected, loop for post participation, then get response and commit state

src/Bundle/ChillPersonBundle/Resources/public/vuejs/AccompanyingCourse/api.js

@@ -4,7 +4,13 @@ const
    , accompanying_period_id = window.accompanyingCourseId //tmp
 ;
 
-// 1. chill_person_accompanying_course_api_show (GET)
+/*
+* Endpoint chill_person_accompanying_course_api_show
+* method GET, get AccompanyingCourse Object
+*
+*  @accompanying_period_id___  integer 
+*  @TODO var is not used but necessary in method signature
+*/
 let getAccompanyingCourse = (accompanying_period_id___) => { //tmp
    const url = `/${locale}/person/api/1.0/accompanying-course/${accompanying_period_id}/show.${format}`;
    return fetch(url)
@@ -14,11 +20,17 @@ let getAccompanyingCourse = (accompanying_period_id___) => { //tmp
       });
 };
 
-// 2. chill_person_accompanying_course_api_add_participation (POST)
-let postParticipation = (accompanying_period_id, person_id) => {
+/*
+* Endpoint chill_person_accompanying_course_api_add_participation, 
+* method POST, add a participation to the accompanyingCourse
+*
+*  @accompanying_period_id integer - id of accompanyingCourse
+*  @person_id integer - id of person
+*/
+let postParticipation = (accompanying_period_id, person_id, method) => {
    const url = `/${locale}/person/api/1.0/accompanying-course/${accompanying_period_id}/participation.${format}`
    return fetch(url, {
-         method: 'POST',
+         method: method,
          headers: {
            'Content-Type': 'application/json;charset=utf-8'
          },