The session ends the end_date at 23.59.59 see BT#7740

Conflicts:
	main/inc/lib/main_api.lib.php
Adding 23:59:59 as  end_date limit see BT#7740

Conflicts:
	main/inc/lib/main_api.lib.php
	main/inc/lib/userportal.lib.php
Merge pull request #28 from DeEvo/7959

Fix bug -refs BT#7959
Adding $_configuration['permissions_teacher_make_course_sessions_drh'] see BT#8049
Teacher can access reporting in a course sessions see BT#8049
Adding c_id in lp_field_values see BT#7975
Merge branch '1.9.x' of github.com:beeznest/chamilo-lms-utp into 7998
Modification to use Units and add c_id to the querys related with field_values - refs BT#7998