feat: 增加首頁評論數顯示

fix: 修復點擊toc後，滾動完toc的highlight在點擊的上一個元素
fix: 修復打賞按鈕Hover的bug close #473
improvement: 友情鏈接界面增加title顯示（top_img設為false時）
improvement: 優化toc顯示，當向上滾動時，導航欄不會遮擋 toc close #472
improvement: 升級facebook comment sdk版本

layout/includes/post/reward.pug

@@ -1,16 +1,16 @@
 .post-reward
-  .reward-button
+  .reward-button.button--animated
     i.fas.fa-qrcode
     = ' ' + _p('donate')
-    .reward-main
-      ul.reward-all
-        each item in theme.reward.QR_code
-          - var clickTo = item.link ? item.link : item.img
-          li.reward-item
-            a(href=url_for(clickTo) target='_blank')
-              if theme.lazyload.enable
-                img.post-qr-code-img(data-lazy-src=url_for(item.img) alt=item.text)
-              else
-                img.post-qr-code-img(src=url_for(item.img) alt=item.text)
-            .post-qr-code-desc=item.text
+  .reward-main
+    ul.reward-all
+      each item in theme.reward.QR_code
+        - var clickTo = item.link ? item.link : item.img
+        li.reward-item
+          a(href=url_for(clickTo) target='_blank')
+            if theme.lazyload.enable
+              img.post-qr-code-img(data-lazy-src=url_for(item.img) alt=item.text)
+            else
+              img.post-qr-code-img(src=url_for(item.img) alt=item.text)
+          .post-qr-code-desc=item.text