AddCalendar creates a new bucket for a tool if it doesn't exist.

DeleteCalendar removes the bucket for a tool if it exists.

FetchCalendars shows a list of the current calendars.

Init opens or creates the database.

NewEvent creates a new Event from the redis mapTODO is this still needed?.

An Event is an allocation of time held by a user.

A Calendar is how we will split events by tools.