[BackgroundUtil] Moved to github flavor

Author: OffRange

app/src/github/java/de/davis/passwordmanager/utils/BackgroundUtil.java

@@ -0,0 +1,13 @@
+package de.davis.passwordmanager.utils;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
+public class BackgroundUtil {
+
+    private static final Executor executor = Executors.newSingleThreadExecutor();
+
+    public static void doInBackground(Runnable runnable){
+        executor.execute(runnable);
+    }
+}