hssqlppp-0.6.0: SQL parser and type checker

SQL parser and type checker, targets PostgreSQL SQL and PL/pgSQL.

Pre alpha: works well and is stable for a subset of SQL, but there are lots of unfinished areas and the api is likely to change a lot from release to release at this time.

Documentation, examples on the homepage: http://jakewheat.github.com/hssqlppp/.

Changes here: https://github.com/JakeWheat/hssqlppp/blob/master/CHANGES