Added several changes to support scheduling, attendance and waitlisting.
https://ten24.teamworkpm.net/tasks/1260883
https://ten24.teamworkpm.net/tasks/1270900
https://ten24.teamworkpm.net/tasks/1270953
https://ten24.teamworkpm.net/tasks/1253122
https://ten24.teamworkpm.net/tasks/1270966
https://ten24.teamworkpm.net/tasks/1271643
https://ten24.teamworkpm.net/tasks/1261591
https://ten24.teamworkpm.net/tasks/1239325
https://ten24.teamworkpm.net/tasks/1233068