Permanent storage of scheduled output

[mrodz]

• Save the result of the scheduling algorithm in the database. #64
• UI for schedules #68
• CRUD on all schedule game fields #126
• Save metadata for schedules games #128
  • Add a table to keep track of field and other metadata for scheduled games, and mock foreign key column on scheduled_game
• Create index on time slots, team ids, region ids
• Export schedule to other formats