Spec:

- web interface
  - create an account
  - grant sirius access to google calendar
- email interface
  - CC sirius on emails when you're arranging to meet someone
    1. sirius checks your calendar for relevant availability
    2. sirius sends email to your contact with options
    3. contact replies with their choice, or asks for more
       options
    4. sirius updates your calendar and notifies you
    
progress so far:

web interface complete except for styling
email interface only allows creation of events by
sending sirius an email with the content of the form
"tennis at tomorrow 6pm"