In an effort to check off items in the Rust API guidelines
checklist (#3632) add an integration test file that tests:
- The location of re-exports for various typical usage styles.
- Regressions in the API surface (things being accidentally moved).
- All public types implement Debug (C-DEBUG).
- For all non-error types:
- `Debug` representation is never empty (C-DEBUG-NONEMPTY)
- For all error types:
- Derive standard traits as defined by `rust-bitcoin` policy.
I used the `cargo check-api` script we have laying around from ages
ago (#2986) to parse `units` and get a list of the public types.
Tobin C. Harding