I'm about 70% done refactoring and rewriting the whole project.
This includes:

- Reorganizing the objrs_macros crate to differentiate between
  parsing code (which parses and validates the macros) and code
  generation (which transforms and emits the code).
- Adding tests (both unit tests and integration tests).
- Revising and adding documentation. I'm still unsure of the best
  way to document attribute macros, but I'd like to continue
  exploring this so that the crate is properly documented.
- Fixing some interactions with ARC. There's still a ton of work
  to do when it comes to object lifetimes and aliasing, but some
  progress has been made.