Add default attributes to migrations

This commit

- adds the default attributes to the generated migrations
- fixes jshint compatibility of the generated migrations
- change the `.complete` handler to `.done`
- fixes #33
I don't think this is going to output proper migrations.

- `id` is `allowNull: false,  primaryKey: true, autoIncrement: true`
- `createdAt` and `updatedAt` are `allowNull: false`

These migrations are going to miss all the `NOT NULL` on every default column, output tables without `id` as the primary key, miss `AUTO_INCREMENT`ing the id, and create `INTEGER` columns in PostgreSQL instead of `SERIAL`.