Provide mechanism for birthday suppression

[mkimberlin]

We need to provide a mechanism to allow members to suppress their birthdays from the main page and the birthdays report.

Acceptance Criteria

• The user profile page provides a toggle to allow a user to express the desire to suppress their birthday
• The value of that toggle is stored in the database
• If the user has expressed a desire to suppress their birthday, then...
  • The user is not included on the Birthdays component used on the main page
  • The user does not show up on the Birthdays report