Add option for provisionally adding a course #270
Description
Maybe the best way to do this is to add a status field to the user schedule.
When the status is something like provisional or disabled or what not, the course would not be passed to the verifier and show up in the UI schedule as grayed out.
Users should be able to enable/disable a course from their schedule view. One option is an eye toggle button that can be closed/opened to disable/enable the course. This can be on the course card itself, but would probably look better on the course popover.
Alternatively, maybe just clicking the course (without dragging) could enable/disable the course. This might be more confusing for users though.