Release 0.8.0:
- use dune to build and install
- ppx: use ppxlib
- ppx: disable warning 39 before the generated code and enable if after

Release 0.7.0:
- add fail_if_not_exist parameter to Ocf.from_file (default is false)

Release 0.6.0:
- upgrade to ocaml 4.12.0, yojson 1.7.0
- checkocaml.ml script handles version number modifiers
- Ocf.to_arg: fix doc string
- fix META file so that ocf.ppx has a version

Release 0.5.0:
- upgrade to OCaml 4.03.0

Release 0.4.0:
- fix: handle change in attribute location in records in ocaml 4.02.2
- configure script does not require camlp4 (which was not used)

Release 0.3.0:
- add Ocf.Wrapper.bool and Ocf.bool to create options with boolean values
- add Ocf.Wrapper.string_map and Ocf.string_map to create options
  whose values are map from string to 'a.
- distinguish open an closed groups (groups and options can only be
  added to open groups)
- add Ocf.as_group to convert an option to a (closed) group
- to_json wrapper functions now have a ?with_doc: bool parameter
- new [@ocf.doc] attribute for record fields to that the wrapper
  generated by ppx extension dump documentation string if with_doc=true

Release 0.2.0:
- (ppx) fix: do not build empty value declarations
- add Ocf.set
- add Ocf.Wrapper.of_ok_error
