Kill autotable - we specify everything anyway
Erradicate nonsensical relationship defaults, switch to a centralized spec

The entirety of the schema is currently switched to:

- cascade update/delete on every FKC
- every FKC is deferrable
- the dbic-side software cascades are disabled on all of update/delete/copy

The only outlier is Track->Talk which is a proper "might_belong_to"
Add a couple obvious relationships (belongs_to part only)
Remove redundant specifications (nullable => 0)
Remove incorrect nullability (signed off by Book)