Created debug menu

app/src/main/res/menu/debug_menu.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item
+        android:id="@+id/clear_local_db"
+        android:title="@string/menu_clear_local_db"/>
+
+</menu>

app/src/main/res/menu/main_menu.xml

@@ -16,7 +16,7 @@
     <item
         android:id="@+id/action_logout"
         android:title="@string/main_menu_logout"
-        android:orderInCategory="100"
+        android:orderInCategory="101"
         app:showAsAction="never"/>
 
 </menu>

app/src/main/res/values/strings.xml

@@ -178,4 +178,8 @@
     <string name="notice_no_conversation">You do not have any conversation yet.</string>
     <string name="notice_no_friend">You do not have any friend yet.</string>
     <string name="err_get_older_conversation_messages">An error occurred while trying to get older messages for the conversation!</string>
+    <string name="preference_debug_mode_title">Enable debug mode</string>
+    <string name="preference_debug_mode_summary">Enable this option to get access to development / debug features.</string>
+    <string name="menu_debug_title">Debug</string>
+    <string name="menu_clear_local_db">Clear local database</string>
 </resources>

app/src/main/res/xml/app_preferences.xml

@@ -8,4 +8,12 @@
         android:title="@string/preference_background_notif_title"
         android:summary="@string/preference_background_notif_summary"/>
 
+
+    <!-- Enable and / or disable debug mode -->
+    <SwitchPreference
+        android:defaultValue="false"
+        android:key="enable_debug_mode"
+        android:title="@string/preference_debug_mode_title"
+        android:summary="@string/preference_debug_mode_summary" />
+
 </PreferenceScreen>