Format redesign

[ricekab]

There is a lot of explicit statements that creates a lot of clutter, especially with JSON format creating a lot of "empty" lines to close scopes.

For 0.4.0 the goal is to allow a more compact description of data objects, to facilitate this some "metadata" tags are being introduced to more clearly specify target classes/packages separately from data objects.

[ricekab]

For the "!models" metatag, allow specifying the module "depth" to scan? Eg:

"!models": ["path.to.package#<depth>"]

[ricekab]

Quick overview of planned metatags:

"!models" to specify source modules / classes to scan and register.
"!files" to specify files, relative to this file, to be imported (one way to allow splitting of data into multiple files).
"!version" to start supporting backward compatibility in case the api changes more. Although this should be relatively rare after 1.0.0 .

Data entries specify their class as their key to limit creating excessively nested scopes.

[ricekab]

"!files" requires knowledge of the original file, which means the seeder would not support direct object conversion. May split up file functionality into a separate seeder that uses a "standard" resolving seeder under the hood.

[ricekab]

Implementation in 4ba55ed (tests are pending).

An extension on the base ResolvingSeeder class is provided to handle file paths.