added error handling to the moderator api in the frontend as requested in #138

static/moderator.js

@@ -17,6 +17,7 @@ var moderator = {
 				dataType: "text",
 				contentType: "application/json",
 				data: JSON.stringify(dict),
+				error: moderator.api.handleapierror,
 				success: function () {
 					if (reload) {
 						window.location.reload();
@@ -32,6 +33,7 @@ var moderator = {
 				dataType: "text",
 				contentType: "application/json",
 				data: JSON.stringify(value),
+				error: moderator.api.handleapierror,
 				success: function () {
 					if (reload) {
 						window.location.reload();
@@ -39,6 +41,9 @@ var moderator = {
 				}
 			})
 		},
+		handleapierror: function(jqXHR, textStatus, errorThrow) {
+			alert("Fehler: "+errorThrow)	
+		},
 		gethttp: function (url){
 			$.ajax({
 				method: "GET",