Git commits in Moodle 3.0.7 by Juan Leyva

commit 388b48ebcd513ec3b92738e7407bd7bcdeaf144b
Author: Juan Leyva <juanleyvadelgado@gmail.com>
Date:   Mon, 07 Nov 2016 20:46:11 +0800
Tag:    v3.0.7

MDL-56268 webservice: Format backtrace to avoid display private datawq

commit f17db49ec61af8b714116b91b6ad506e85abe74e
Author: Juan Leyva <juanleyvadelgado@gmail.com>
Date:   Fri, 04 Nov 2016 23:51:05 +0800
Tag:    v3.0.7

MDL-56765 webservice: After a new session is started unset old preferences

commit 396f819ce7848dcbef054c74a37a270d99596710
Author: Juan Leyva <juanleyvadelgado@gmail.com>
Date:   Thu, 22 Sep 2016 17:52:11 +0800
Tag:    v3.0.7

MDL-56065 user: Fix update_users Web Service