Git commits in Moodle 3.5.2 by Tim Schroeder

commit 4c66ff31c8efde2bd8d8f4635dfcaa2dc5cf1a7b
Author: Tim Schroeder <t.schroeder@itc.rwth-aachen.de>
Date:   Mon, 16 Jul 2018 23:20:36 +0800
Tag:    v3.5.2

MDL-61351 auth_shibboleth: removed redundant session handler class check

commit 2542cb94e4048eda23afae3058186b4d82e7d979
Author: Tim Schroeder <t.schroeder@itc.rwth-aachen.de>
Date:   Mon, 16 Jul 2018 23:19:40 +0800
Tag:    v3.5.2

MDL-61351 core: added \core\session\manager\get_handler_class()

commit 4b1adeef8dc475c392085cab9c5aaea63f754127
Author: Tim Schroeder <t.schroeder@itc.rwth-aachen.de>
Date:   Wed, 04 Jul 2018 23:56:11 +0800
Tag:    v3.5.2

MDL-61351 shibboleth: Logout: fix session handler class not being used