Make My Course list more generic

[Jeremy Hopkins]

Change the admin setting for mysitessortoverride to a drop down list.

Add option to use a list of strings to identify current courses.

This would allow organisations naming courses with "2015", "2015/16" etc for academic year to be able to collapse past courses into a sub menu.

[Jeremy Hopkins]

Fix #361 adding more options to order the my courses / my sites list

→ <<cset 8241920e5bd3>>