Fix tpl files: php tags, add @file, reference orginal file

The *.tpl.php files have problems:

• Do not open and close php tags
• Do not contain @file
• Would be helpfull to indicate source tpl file
• Remove box.tpl.php which is no longer used

This patch fixes the listed issues. There is no clear standard for linking to the original tpl file so I have followed the guidance of the follwoing issues:
#292074: Documentation error: included themes do not document tpl.php files
#782016: Need doxygen standards for overriding a theme hook/template