breaking changes: widget 寫法更改/可添加非sticky區域widget

feat: 升級facebook comment js 到 v10
fix: 修復當內容過少時， footer 沒有底部靠攏的bug
improvement: 404頁面不再顯示 rightside

layout/includes/404.pug

@@ -1,7 +1,7 @@
 - var top_img = theme.error_404.background || theme.default_top_img
 - var bg_img = `background-image: url('${url_for(top_img)}')`
 
-#body-wrap.error
+#body-wrap.error404
   div(style='display: none')
     include ./header/index.pug
 

layout/includes/third-party/comments/facebook_comments.pug

@@ -7,7 +7,7 @@ script.
     if (typeof FB === 'object') FB.XFBML.parse()
     else {
       let ele = document.createElement('script')
-      ele.setAttribute('src','https://connect.facebook.net/!{theme.facebook_comments.lang}/sdk.js#xfbml=1&version=v9.0')
+      ele.setAttribute('src','https://connect.facebook.net/!{theme.facebook_comments.lang}/sdk.js#xfbml=1&version=v10.0')
       ele.setAttribute('async', 'true')
       ele.setAttribute('defer', 'true')
       ele.setAttribute('crossorigin', 'anonymous')

layout/includes/third-party/comments/waline.pug

@@ -13,7 +13,7 @@ script.
         emojiCDN: '#{theme.waline.emojiCDN}',
         emojiMaps: !{emojiMaps},
         visitor: #{theme.waline.visitor},
-        dark: '[data-theme="dark"]'
+        dark: 'html[data-theme="dark"]'
       }, !{JSON.stringify(theme.waline.option)}))
     }