add a title plus summary to "Use Tor" preference

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

@@ -64,5 +64,5 @@
     <string name="detailThumbsDownImgViewDescription">Dislikes</string>
     <string name="detailThumbsUpImgViewDescription">Likes</string>
     <string name="useTor">Use Tor</string>
-    <string name="useTorTitle">Proxy connections via The Onion Router</string>
+    <string name="useTorSummary">Force download traffic through Tor for increased privacy (streaming videos not yet supported)</string>
 </resources>

app/src/main/res/xml/settings_screen.xml

@@ -74,7 +74,8 @@
 
         <CheckBoxPreference
             android:key="@string/useTor"
-            android:title="@string/useTorTitle"
+            android:title="@string/useTor"
+            android:summary="@string/useTorSummary"
             android:defaultValue="false"/>
 
     </PreferenceCategory>