Fixed multiple bugs / Added new features

【Contents of fix】
■Fixed a bug where the theme options “Top Page” > “Blog List Settings” > “Number of Posts to Display” was blank.
■Fixed an issue where the color settings in the theme options “Marketing” > “Footer CTA” were not reflected.
■Added a new theme option “Custom Script”.
■Added a new theme option “CTA Settings for Archive Pages”.
■Added new theme option “Post Title Hover Color”.
■Fixed the wording of theme options.
■Fixed the site search function so that contents created with Page Builder are also searchable.
■Fixed a bug that the preview may not work properly on pages using Page Builder.
■Support for WP5.1.1

The following files have been modified for this update.
【Fixed files】
admin/inc/basic.php
admin/inc/blog.php
admin/inc/front_page.php
admin/js/my_script.js
functions/footer-cta.php
functions/head.php
languages/ja.mo
languages/ja.po
pagebuilder/assets/admin/css/admin.css
pagebuilder/assets/admin/js/admin.js
pagebuilder/assets/css/googlemap.css
pagebuilder/modules/includes/slick.php
pagebuilder/modules/slider.php
pagebuilder/pagebuilder.php
footer.php
functions.php
style.css