Revision history for PostgreSQL extension explanation.

0.3.0   2011-04-30T00:12:09
      - Fixed GitHub links in `META.json`.
      - Added abstract to the `provides` section of `META.json`.
      - Fixed the Markdown formattin of `psql` output in the documentation so
        that the results properly appear in a `<pre>` block.
      - Enabled the `VERBOSE` parameter to the internal call to `EXPLAIN`.
        This populates a few more columns that were otherwise always `NULL`,
        especially the `schema` and `output` columns.
      - Enabled the BUFFERS parameter to the internal call to `EXPLAIN
        ANALYZE`. This populates a few more columns that were otherwise always
        `NULL`, namely those ending in `_blocks`.
      - Added PostgreSQL 9.1 `CREATE EXTENSION` support, including migration
        from an unpackaged install via `CREATE EXTENSION semver FROM
        unpackaged`.

0.2.0   2011-02-21T20:14:15
      - Renamed from "exlain-table" to "explanation". Suggested by Andrew
        Dunstan.
      - Renamed `plan()` to `explanation()`.
      - Improved the documentation.
      - Released on PGXN under the revised BSD open source license.

0.1.0   2011-01-07T23:04:43
      - Initial version.
      - Written by PGX for Marchex.
      - Not otherwise released.