The changes affecting Lwt_ppx are also released concurrently as Lwt_ppx
1.1.0.

Bugs fixed

- Restore backtrace support (#554, #556, Gabe Levi).
- Serious logic error that could cause Lwt to hang or crash (#549,
  reported @koen-struyve).
- All `Lwt_list` functions are now tail-recursive (#538, Joseph Thomas).

Additions

- Support `;%lwt` syntax in the PPX (#307, Hezekiah Carty).
- `Lwt_stream.iter_n` (#312, Hezekiah Carty).

Miscellaneous

- Testing improvements (#536, #541, @cedlemo).
- Documentation improvements (#544, #546, #547, #553, #559, Daniil
  Baturin, Jason Evans, Jess Smith, Milo Turner).