Retry Open Meteo API when overloaded

src/pkjs/weather.js

@@ -2,13 +2,26 @@ function weatherFailure() {
     Pebble.sendAppMessage({ PKJS_TEMP_BAR_COUNT: -1 });
 }
 
-var xhrRequest = function (url, type, callback) {
+var xhrRequest = function (url, type, callback, retries) {
+    if (retries === undefined) {
+        retries = 2;
+    }
     var xhr = new XMLHttpRequest();
     xhr.timeout = 7500;
     xhr.onload = function () {
-        if (xhr.status === 200) {
+        switch (xhr.status) {
+            case 200:
                 callback(this.responseText);
-        } else {
+                break;
+            case 503:
+                if (retries > 0) {
+                    setTimeout(function () {
+                        xhrRequest(url, type, callback, retries - 1);
+                    }, 5000);
+                    break;
+                }
+            // fallthrough
+            default:
                 weatherFailure();
         }
     };