start a new foreground service when the stopwatch is active and the app is moved to the background

app/src/main/res/values-zh-rCN/strings.xml

@@ -7,6 +7,7 @@
     <string name="label">标签</string>
     <string name="no_days_selected">未选择哪一天</string>
     <string name="timer">定时器</string>
+    <string name="stopwatch">Stopwatch</string>
     <string name="lap">分段</string>
     <string name="stopwatch_stopped">秒表已停止</string>
     <string name="timer_stopped">定时器已停止</string>
@@ -69,4 +70,4 @@
         Haven't found some strings? There's more at
         https://github.com/SimpleMobileTools/Simple-Commons/tree/master/commons/src/main/res
     -->
-</resources>
+</resources>