dirname() is a slow function compared with __DIR__ and using
'/../'.  Moodle has a large number of legacy files that are included
each time a page loads and is not able to use an autoloader as it is
functional code.  This allows those required includes to perform as
best as possible in this situation.

Based on a patch by Matthew Cannings, this replaces Book's previous/next arrow
image links with a choice of: no links, image links, or chapter title text links.

Remove old FEATURE_GROUPMEMBERSONLY as no longer required.

AMOS START
 MOV [neverseen, mod_folder],[neverseen, report_outline]
 MOV [neverseen, mod_page],[neverseen, report_outline]
 MOV [neverseen, mod_resource],[neverseen, report_outline]
 MOV [neverseen, mod_url],[neverseen, report_outline]
AMOS END

This reverts commit 7b7bb92d.

In new logging api, xxx_get_view_actions() and xxx_get_post_actions()
will not be used to identify the paticipation of user. Event's crud
and edulevel status will define user's participation.