TODO

0.410000
[X] Add additional relationships in load_sims call
[ ] Subroutine as a value
[ ] __META__ => { label => 'bar' } ---> Foo{bar}

ZR fixes
[ ] Create a test that has the parent in a multi-column UK
[ ] Add option to use random parent instead of first parent
    * There's a stash entry for this
[ ] info->{nullable} vs !info->{is_nullable}
[ ] create_item() local$@
[ ] Create a test that has the parent in multiple UK's
[ ] Create a test that has multiple has_many back (dies)
[ ] Create a test that has no has_many back (dies)
[ ] A column is in multiple relationships and has a backreference

[ ] Switch seed randomization to Math::Random instead of rand(time&$$)

General fixes
[ ] Add auto-generation of:
    [ ] negative values
    [ ] enum/set (based on values from database)
    [ ] json (is this even reasonable?)
[ ] Oracle RAW(16) doesn't get read correctly.
[ ] Add a test where the table's PK has no auto-increment
    * This should be handled by not-null + unique, but just verify.
[ ] Add children to meet to level of constraint
    [ ] Document constraints better (?)
[ ] Provide a sim function that can use back-references
    [ ] to other columns of this row

[X] Test for a relationship with a subroutine
[X] Add auto-generation of:
    [X] datetime values
[X] Handle the case where a FK is also a UK
[X] Add ability to use relationships of Sims references
  * \'Foo[0].rel1.meth1.rel2.meth2'
[X] Add optional error when using column of a relationship
[X] Add UKFK that is a backref
[X] Hoist the number/hashref->arrayref conversion to all levels
[X] Add references in strings for relationship names
[X] Catch circular references
    [X] Successive attempts to create the same thing (maintain a stack?)
[X] Generalize handling of column types to numeric, decimal, and character.
    * Right now, only "int" and "varchar" are handled.
    * Also error out when a non-NULL column with an unknown type happens
[X] Don't require cycle-breaking with nullable FKs