2018-02-26: release 1.6.4
  [compat] Tests should now work with older versions of jbuilder.

2018-02-21: release 1.6.3
  [compat] Fix tests.

2018-01-25: release 1.6.1
  [compat] Emit line directives always containing the file name,
           as mandated starting with ocaml 4.07.

2017-08-07: release 1.6.0
  [pkg] BREAKING: cppo and cppo_ocamlbuild are now two distinct opam
        packages.

2017-04-24: release 1.5.0
  [+ui] Added the `CAPITALIZE()` function.

2016-08-19: release 1.4.0
  [compat] Cppo is now safe-string ready.

2016-04-20: release 1.3.2
  [pkg] Cppo can now be built on MSVC.

2015-09-20: release 1.3.1
  [bug] Possible to have #endif between two matching parenthesis.

2015-09-13: release 1.3.0
  [+ui] Removed the need for escaping commas and parenthesis in macros.
  [+ui] Blanks is now allowed in argument list in macro definitions.
  [+ui] #directive with wrong arguments is now giving a proper error.
  [bug] Fixed expansion of __FILE__ and __LINE__.

2014-11-10: release 1.1.2
  [+ui] Ocamlbuild_cppo: added the ocamlbuild flag `cppo_V(NAME:VERSION)`,
        equivalent to `-V NAME:VERSION` (for _tags file).

2014-11-10: release 1.1.1
  [+ui] Ocamlbuild_cppo: added the ocamlbuild flag `cppo_V_OCAML`,
        equivalent to `-V OCAML:VERSION` (for _tags file).

2014-11-04: release 1.1.0
  [+ui] Added the `-V NAME:VERSION` option.
  [+ui] Support for tuples in comparisons: tuples can be constructed
        and compared, e.g. `#if (2 + 2, 5) < (4, 5)`.

2014-10-20: release 1.0.1
  [+ui] `#elif` and `#else` can now be used in the same #if-#else statement.
  [bug] Fixed the Ocamlbuild flag `cppo_n`.

2014-09-06: release 1.0.0
  [bug] OCaml comments are now better parsed. For example, (* '"' *) works.

2014-06-10: release 0.9.4
  [+ui] Added the ocamlbuild_cppo plugin for Ocamlbuild. To use it:
        `-plugin(cppo_ocamlbuild)`.

2012-02-03: release 0.9.3
  [pkg] New way of building the tar.gz archive.

2011-08-12: release 0.9.2
  [+ui] Added two predefined macros STRINGIFY and CONCAT for making
        string literals and for building identifiers respectively.

2011-07-20: release 0.9.1
  [+ui] Added support for processing sections of files using external programs
        (#ext/#endext, -x option)
  [doc] Moved and extended documentation into the README file.

2009-11-17: initial version 0.9.0
