App preview UI update

Introducing 7.2 with brand new preview UI.

Author: mgks

docs/index.html

@@ -95,7 +95,7 @@ <h3><span class="icon">🧩</span> More Features You Can Use</h3>
 </main>
 
 <footer class="app-footer">
-	<a href="https://github.com/mgks/Android-SmartWebView/issues">Submit Issues / Join Discussion</a>
+	<a href="https://github.com/mgks/Android-SmartWebView/issues" target="_blank">Submit Issues / Join Discussion</a>
 	<br />
 	<b>Smart WebView v7.2</b>
 </footer>