Author: Tom Dickman
MDL-64901 block_myoverview: admin settings to control available layouts
Added an admin setting which allows the administrator to set the available layouts for users and which
defaults to all layouts being available, or the card layout only if no layouts are enabled.
If only one layout is enabled, the dropdown `nav-display-selector` template will not be displayed as
it can no longer be utilised.
If the user preference is set to a layout that is no longer available, this is ignored and the first
available layout defaulted to.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=5f59a4c0630dcef474ba22f33967624b3ea9939f
http://github.com/moodle/moodle/commit/5f59a4c0630dcef474ba22f33967624b3ea9939f
+ 3.8 en [layouts,block_myoverview]
+ 3.8 en [layouts_help,block_myoverview]