Optimized rate limiter implementation

- Moved rate limiter scope into proxy router
- Give IpTable a better name following clean code guideline
- Optimized client IP retrieval method
- Added stop channel for request counter ticker
- Fixed #199
- Optimized UI for rate limit

src/web/components/status.html

@@ -74,7 +74,7 @@
         <input type="text" id="incomingPort" placeholder="Incoming Port" value="80">
         <button class="ui green notloopbackOnly button" style="background: linear-gradient(60deg, #27e7ff, #00ca52);" onclick="handlePortChange();"><i class="ui checkmark icon"></i> Apply</button>
     </div>
-    <br><br>
+    <br>
     <div id="tls" class="ui toggle notloopbackOnly checkbox">
         <input type="checkbox">
         <label>Use TLS to serve proxy request</label>