Multiple bug fixes

【Contents of fixes】
■Added support for WP5.6 (compatible with jQuery version upgrade)
■Added h1 tag to top page, archive page and fixed page

The following are the files that have been modified for this update.
【Modified file】
admin/js/my_script.js
archive-gallery.php
archive-news.php
functions.php
functions/head.php
functions/logo.php
functions/ogp.php
index.php
page-lp.php
page.php
style.css
taxonomy-gallery_category.php

【Added files】
js/jquery.easing.1.4.js