Multiple bug fixes

【Contents of the fix】
■【Mac】Fixed a bug that the thickness of Japanese and European characters may be displayed differently when using some fonts.
■Fixed an error regarding the login judgment in the comment section.
■Social Button Type 5 (Official Button) “Facebook Like Button” specification change.
■Removed “Google+” from the social button settings.

The following are the files that have been modified for this update.

【Modified files】
admin/theme-options.php
+comments.php
editor-style.css
functions/custom_page_link.php
functions/update_notifier.php
japanese.css
sns_btn_btm.php
sns_btn_top.php
style.css