Added functions / fixed multiple bugs

【Contents of the fix】
■Changed specifications to allow custom CSS, custom scripts, and SEO settings (meta tags) for individual posts.
■Fixed a bug in TCD Theme > Speed Up that Google Map would not display when “Use Lazyload” was set.
■Adjusted the display position of Googlemap custom markers.
■Fixed an issue where the layout of the design content of the fixed page template “Design Page 1” would be broken on smartphones when the layout is set to “Display left side image lowered”.

The following are the files that have been modified for this update.
【Modified file】
comments.php
css/responsive.css
functions.php
functions/acceleration.php
functions/custom_css.php
functions/custom_script.php
functions/head.php
languages/ja.mo
languages/ja.po
style.css