A ton of changes for our new workshift policy

A quick summary:

 - For the purposes of this update, "Working Members" are members with a
   work status of "Workshift" or "Committee"
 - Working members now receive 31 "discount days" after successfully working a
   shift
 - The dashboard and member pages now reflect when a working member's discount
   will expire.
 - The timecard has been updated. No more Hours Worked. Terms have been
   renamed to reflect language of new policies.
 - When a working member's discount expires, the Member.discount
   property/function now returns 5 (as in 5% similar to non-working
   members)