Revision history for PostgreSQL extension semver.

0.2.1 2011-04-20T20:37:05
      - Fixed the metadata file to reflect that the "pair" extension is not
        included in the semver distribution.
      - Added abstract and doc file to the `provides` section of `META.json`.
      - Removed the `NO_PGXS` stuff from `Makefile`, as the PostgreSQL core
        team does not recommend its use outside of the core contrib
        extensions.
      - Added PostgreSQL 9.1 `CREATE EXTENSION` support, including migration
        from an unpackaged install via `CREATE EXTENSION semver FROM
        unpackaged`.
      - Renamed `doc/semver.md` to `doc/semver.mdd`, so that PGXN will parse
        it as MultiMarkdown. This will allow the tables to be properly
        formatted.
      - Removed documentation that semver is implemented as a domain. It
        hasn't been since 0.2.0.
      - Removed Unicode characters `psql` output in the documentation.

0.2.0 2011-02-05T19:32:49
      - Converted to a native type implemented in C by Sam Vilain. While David
        was at lunch, no less.
      - As a consequence, `USING` is no longer required in an `ORDER BY`
        clause to get proper semver sort ordering.
      - Added casts from nuermic types.
      - Renamed `clean_semver()` to `to_semver()`.

0.1.0  2010-10-07 18:31:43
      - Initial version.
      - Implementation in pure PL/pgSQL.
      - Included in [PGXN Manager](https://github.com/theory/pgxn-manager).
      - Not otherwise released.