Chore: HTTPS links in _config.yml

Close #847

Author: coliff

_config.yml

@@ -11,7 +11,7 @@ language:
 timezone:
 
 # URL
-## If your site is put in a subdirectory, set url as 'http://yoursite.com/child' and root as '/child/'
+## If your site is put in a subdirectory, set url as 'https://yoursite.com/child' and root as '/child/'
 url: /
 root: /
 permalink:
@@ -50,7 +50,7 @@ tag_map:
 # Date / Time format
 ## Hexo uses Moment.js to parse and display date
 ## You can customize the date format as defined in
-## http://momentjs.com/docs/#/displaying/format/
+## https://momentjs.com/docs/#/displaying/format/
 date_format: YYYY-MM-DD
 time_format: HH:mm:ss