Adding the OGP setting function and dealing with bugs caused by browser updates

【Contents of fixes and feature additions】
■Added OGP setting function to theme options (Facebook/Twitter)
■Fixed a bug that caused the load icon to flicker in the latest version of firefox.

The following files have been modified for this update.
【Fixed files】
admin/theme-options.php
footer.php
functions.php
functions/head.php
header.php
languages/ja.mo
languages/ja.po
style.css

The following files have been added for this update.
【Added files】
functions/ogp.php

For more information, please visit the IZM (tcd034) download site for purchasers.