Distribution 1.2.0

CHANGES:

- Add keyword completion

- Add go to declaration functionality to jump to a value's specification in a
  .mli file (ocaml#294)

- ocaml#245: correctly use mutexes on OpenBSD (ocaml#264)

- ocaml#268: Do not use vendored libraries when building the lsp package (ocaml#260)

- ocaml#271: Clear diagnostics when files are closed

- Disable non-prefix completion. There's no reliably way to trigger it and it
  can be slow.

Distribution 1.1.0

CHANGES:

- Implement a command to switch between module interfaces and implementations
  (ocaml#254)

- Do not crash on invalid positions (ocaml#248)

- add missing record fields to list of completions (ocaml#253)

- do not offer `destruct` as a code action in interface files (ocaml#255)