Support refresh routing rules

Useful when VPN interface has changed.

mobile/src/main/res/drawable/ic_navigation_refresh.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#fff"
+        android:pathData="M17.65,6.35C16.2,4.9 14.21,4 12,4c-4.42,0 -7.99,3.58 -7.99,8s3.57,8 7.99,8c3.73,0 6.84,-2.55 7.73,-6h-2.08c-0.82,2.33 -3.04,4 -5.65,4 -3.31,0 -6,-2.69 -6,-6s2.69,-6 6,-6c1.66,0 3.14,0.69 4.22,1.78L13,11h7V4l-2.35,2.35z"/>
+</vector>

mobile/src/main/res/menu/main.xml

@@ -1,6 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
       xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/reapply"
+        android:icon="@drawable/ic_navigation_refresh"
+        android:title="Reapply routing rules"
+        app:showAsAction="always"/>
     <item
         android:id="@+id/settings"
         android:icon="@drawable/ic_action_settings"

mobile/src/main/res/xml/pref_settings.xml

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
     <PreferenceCategory
-        android:key="service"
         android:title="Service">
         <be.mygod.vpnhotspot.preference.AlwaysAutoCompleteEditTextPreference
             android:key="service.upstream"
@@ -18,10 +17,6 @@
             android:title="Downstream DNS server:port"
             android:summary="%s"
             android:defaultValue="8.8.8.8:53"/>
-        <Preference
-            android:key="service.clean"
-            android:title="Clean up"
-            android:summary="Remove routing rules"/>
     </PreferenceCategory>
     <PreferenceCategory
         android:title="Misc">