Feat: Add sina weibo option to social block in sidebar settings (#456)

Author: shawnlinboy

_config.yml

@@ -164,6 +164,7 @@ site_state: true
 #social:
   #GitHub: https://github.com/yourname || github
   #E-Mail: mailto:yourname@gmail.com || envelope
+  #Weibo: https://weibo.com/yourname || weibo
   #Google: https://plus.google.com/yourname || google
   #Twitter: https://twitter.com/yourname || twitter
   #FB Page: https://www.facebook.com/yourname || facebook