Author: Alexander Bias
MDL-66133 user: Add setting to configure user filters
http://git.moodle.org/gw?p=moodle.git;a=commit;h=a292ed54728d70b233e6fbf8401fcb58be3fbd16
http://github.com/moodle/moodle/commit/a292ed54728d70b233e6fbf8401fcb58be3fbd16
+ 3.8 en [userfiltersdefault,core_admin]
+ 3.8 en [userfiltersdefault_desc,core_admin]
+ 3.8 en [usermanagement,core_admin]