PHP7 support and others

【Corrections】
■Support for PHP7
■Fixed an error that sometimes appears in the theme options screen.

The following files have been modified for this update.
【Fixed files】
admin/theme-options.php
widget/ad.php
widget/category_list.php
widget/styled_post_list1.php
widget/styled_post_list2.php
style.css

For more information, please visit the download site for purchasers of INNOVATE HACK (tcd025).