Package resource dependencies

[fydar]

Create a mechanism for resource importers to register dependencies of one resource to another.

Create an API for resources that iterates all resources that are dependent on one resource and iterates all resources that a resource is dependant on.

Report errors during the build pipeline if dependencies could not be located.

Report errors during the loading pipeline if dependencies could not be located.

First implementation of dependencies won't be cross-project, it's likely this will be a separate Github issue.

[fydar]

The first-pass has been implemented, however, it will require reworking as I expand the import pipeline to introduce resource dependencies in edit-time.