Create a steward signup page for events

[git-wil]

Goal

Create a page accessible to stewards used to sign up for upcoming events. This will allow head stewards to have an log of who has/will be able to attend events.

Subtasks

• Create a new DB collection for internal events, which should include
  • the event name
  • a description of the event
  • date/time
  • number of stewards needed
  • list of steward proficiencies that are needed/wanted for the event
  • list of stewards signed up for event
• Implement a way to modify and add new events in the management console, which would look something akin to the workshop creation tab
• Modify the steward resources tab to include a table of upcoming events and allow people to click to signup
• automated email reminders would also be nice