Git commits in Moodle 3.3.4 by sam marshall

commit d51a8d2e4039a7380d2c6e47f450d1d15323ae89
Author: sam marshall <s.marshall@open.ac.uk>
Date:   Fri, 01 Dec 2017 23:14:55 +0800
Tag:    v3.3.4

MDL-60943 core_search: Improve exception for preg_replace errors


commit de874ead3997fc8b9799785d3d6e4f35853d7751
Author: sam marshall <s.marshall@open.ac.uk>
Date:   Fri, 17 Nov 2017 00:50:08 +0800
Tag:    v3.3.4

MDL-60838 core_search: File upload does not honour timeout