Feature request: Hide course catalog for unauthenticated users/guests

[MuPp3t33r]

I think it would be nice if site admins can, by way of a config option perhaps something like (illustrative example) MFE_CONFIG['HIDE_COURSE_LIST_UNAUTHENTICATED'], such that any guest/unauthenticated user will not see the list of courses until they are signed in, with a default value of false/disabled so as to not change the standard way of showing courses, but this will allow an admin to decide if they want courses to be viewed by anyone without authenticating.