Django-rest-tsg

* Add task-level build_dir support

* Enrich README content
* Add builder logging
* Fix alias failure
* Fix aliases in typescript import statements

* Get dataclass of DataclassSerializer from dataclass attribute when Meta is missing.
* Fix field type of trivial serializer

* Fix annotated trivial type fallback.
* Skip ``typing`` types on dependency resolving.

The first step is hardest.