Bug/calender (#1558)

* fixes calendar not rendering when toggling view

* same for po

* and builds

InvenTree/build/templates/build/index.html

@@ -158,6 +158,8 @@ $('#view-calendar').click(function() {
     
     $("#build-order-calendar").show();
     $("#view-list").show();
+
+    calendar.render();
 });
 
 $("#view-list").click(function() {

InvenTree/order/templates/order/purchase_orders.html

@@ -146,6 +146,8 @@ $('#view-calendar').click(function() {
     
     $("#purchase-order-calendar").show();
     $("#view-list").show();
+
+    calendar.render();
 });
 
 $("#view-list").click(function() {

InvenTree/order/templates/order/sales_orders.html

@@ -141,9 +141,11 @@ $('#view-calendar').click(function() {
     $(".columns-right").hide();
     $(".search").hide();
     $('#filter-list-salesorder').hide();
-    
+
     $("#sales-order-calendar").show();
     $("#view-list").show();
+
+    calendar.render();
 });
 
 $("#view-list").click(function() {