Option to choose what sections appear on the student Dashboard

**Is your feature request related to a problem? Please describe.**
Currently you can remove the endpoint for a section (like Memberships) and the "My Memberships" option will disappear from the menu, along with removing the "View All Memberships" button on the Dashboard. However there's currently no option to completely hide the section on the Dashboard, you need to uses CSS or customize the template.

**Describe the solution you'd like**
An option to choose what sections to have on the Dashboard, with all of them there by default. Perhaps checkboxes beside the existing endpoint options or a separate settings location where you can choose what sections you want to keep, and drag/drop to re-order them.


**Describe alternatives you've considered**
When an endpoint is cleared, also clear that section on the dashboard. However this is very different to how it works now with no real way to ensure backwards compatibility, and removing an endpoint doesn't necessarily mean the user wants to hide it on the Dashboard itself.