Author: Jerome Mouneyrac
MDL-28990 add web service mobile overview
http://git.moodle.org/gw?p=moodle.git;a=commit;h=fc218ba9e2879ad15eee2f909d14cb5c038c2e51
http://github.com/moodle/moodle/commit/fc218ba9e2879ad15eee2f909d14cb5c038c2e51
+ 2.1 en [enablemobilewsoverview,core_webservice]
+ 2.1 en [mobilewsdisabled,core_webservice]
+ 2.1 en [mobilewsenabled,core_webservice]