Updating the OPAM

[richard-zhang]

Could you do a release on the current version on the master?

I can see the current version available on OPAM is not updated hence not compatible with 4.14 above compiler.

[ksromanov]

Second the request. Please update OPAM version.

[hanshoglund]

IIUC code changes changes (not just release) are required for 4.14 support.

For example Pext_decl now takes 3 arguments instead of 2. Here is an example of a cross-version solution: ocamllibs/metapp@713257f

[hanshoglund]

Made a PR to reflect the current state #91

[yakobowski]

I have updated the code to OCaml 4.14 in #95. However, I have not used a lib to make the code multi-versions compatible. I don't think anything nice exists for pattern-matching-based code, and this is what Camelot mostly uses. (The AST is read, but not created.)