resolves: #1207 make daily contact backup string translatable

src/main/res/values/strings.xml

@@ -60,6 +60,7 @@
     <string name="prefs_calendar_contacts_address_resolve_error">Server address for account could not be resolved for DAVdroid</string>
     <string name="prefs_calendar_contacts_no_store_error">Neither F-droid nor Google Play is installed</string>
     <string name="prefs_calendar_contacts_sync_setup_successful">Calendar &amp; contacts sync set up</string>
+    <string name="prefs_daily_contacts_sync_summary">Daily backup of your contacts</string>
     <string name="prefs_help">Help</string>
     <string name="prefs_recommend">Recommend to friend</string>
     <string name="prefs_feedback">Feedback</string>

src/main/res/xml/preferences.xml

@@ -111,7 +111,7 @@
 		<Preference
 			android:title="@string/actionbar_contacts"
 			android:key="contacts"
-			android:summary="Daily backup of your contacts"/>
+			android:summary="@string/prefs_daily_contacts_sync_summary"/>
 		<Preference android:title="@string/prefs_help" android:key="help" />
 		<Preference android:title="@string/prefs_recommend" android:key="recommend" />
 		<Preference android:title="@string/prefs_feedback" android:key="feedback" />