Set first day of week to international standards

aleksis/core/frontend/components/calendar/CalendarOverview.vue

@@ -84,6 +84,7 @@
             no-title
             v-model="calendarFocus"
             :style="{ margin: '0px -8px' }"
+            :first-day-of-week="1"
           ></v-date-picker>
           <v-list flat subheader>
             <v-subheader>
@@ -116,6 +117,7 @@
               :events="events"
               :type="currentCalendarType"
               :event_color="getColorForEvent"
+              :weekdays="[1, 2, 3, 4, 5, 6, 0]"
               @click:date="viewDay"
               @click:day="viewDay"
               @click:more="viewDay"