Add dividers and icons to advanced prefs

app/src/main/res/xml/preferences_advanced.xml

@@ -1,20 +1,20 @@
 <?xml version="1.0" encoding="utf-8"?>
-<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
+  xmlns:app="http://schemas.android.com/apk/res-auto">
 
   <Preference
+    android:icon="@drawable/ic_outline_attachment_24px"
     android:key="@string/p_attachment_dir"
     android:title="@string/attachment_directory" />
 
-  <Preference
-    android:key="@string/EPr_manage_purge_deleted"
-    android:title="@string/EPr_manage_purge_deleted" />
-
   <SwitchPreferenceCompat
     android:defaultValue="true"
+    android:icon="@drawable/ic_outline_event_24px"
     android:key="@string/p_end_at_deadline"
     android:summaryOff="@string/EPr_cal_end_at_due_time"
     android:summaryOn="@string/EPr_cal_start_at_due_time"
-    android:title="@string/EPr_cal_end_or_start_at_due_time" />
+    android:title="@string/EPr_cal_end_or_start_at_due_time"
+    app:allowDividerAbove="true" />
 
   <SwitchPreferenceCompat
     android:defaultValue="false"
@@ -30,6 +30,12 @@
     android:key="@string/EPr_manage_delete_all_gcal"
     android:title="@string/EPr_manage_delete_all_gcal" />
 
+  <Preference
+    android:icon="@drawable/ic_outline_delete_24px"
+    android:key="@string/EPr_manage_purge_deleted"
+    android:title="@string/EPr_manage_purge_deleted"
+    app:allowDividerAbove="true" />
+
   <Preference
     android:key="@string/EPr_reset_preferences"
     android:title="@string/EPr_reset_preferences" />