Allow Roundup to use PostgreSQL database native full text search back_postgreql.py - schema version changes for schema version 7. configuration.py - added indexer_language checks for postgresql. Hardcoded list for now. Docs admin_guide and upgrading Tests. This also restructures the version upgrade tests for the rdbms backends. They can run all of them now as the proper cascade is developed to roll back changes to version 6.

# make this dir a package