reorder menus, cleanup code, add experimental tab activity

OpenPGP-Keychain/res/layout/lists_activity.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical" >
+
+    <LinearLayout
+        android:id="@+id/lists_tabs_container"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical" />
+
+</LinearLayout>