base: Add Mafiasi.is_guest field
registration: Move account creation in own function
guests: First draft of this app
base: Add TokenExceeded.get_message to tocket bucket implementation
base: Make TokenExceeded.get_message timezone-aware
base: Restructured token bucket
guests: Add limits for invitations
guests: Handle existing email addresses
guests: Fix unused import in models.py
guests: Fix AttributeError in models.py
guests: Add missing template guests/has_account.html