Add Missing helper methods...

build.gradle

@@ -1505,3 +1505,22 @@ def getSecondaryArtifacts() {
     if (apiPackage) secondaryArtifacts += [apiJar]
     return secondaryArtifacts
 }
+
+def getURL(String main, String fallback) {
+    return pingURL(main, 10000) ? main : fallback
+}
+
+// credit: https://stackoverflow.com/a/3584332
+def pingURL(String url, int timeout) {
+    url = url.replaceFirst("^https", "http") // Otherwise an exception may be thrown on invalid SSL certificates.
+    try {
+        HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection()
+        connection.setConnectTimeout(timeout)
+        connection.setReadTimeout(timeout)
+        connection.setRequestMethod("HEAD")
+        int responseCode = connection.getResponseCode()
+        return 200 <= responseCode && responseCode <= 399
+    } catch (IOException ignored) {
+        return false
+    }
+}