Added get_lang_code().
Drafting course.php.
Merge remote-tracking branch 'origin/master'
Minor stylistic changes.
Working on course.php…
Added convenience functions in_array() and equals().
Drafting course.php; will now test…
Moved to ./unused.
Moved Session-related exit_with_result() and exit_with_error() from APIUser.php to Session.
Various corrections, modifications, improvements.
Consolidations.
Merge remote-tracking branch 'origin/master'