Working out outdated migrations

Several migrations were failing when running db:migrate at the initial release version from an empty database.  These changes took out statements that were causing migrations to fail, usually because of references to models that no longer exist.

Understood that the vagrant vm is kinda unofficially the only thing recommended at this stage, but it was trivial to get db:migrate to move with no problems, and all tests green from a working rvm/ruby and postgres.app on OS X 10.7.

Added `CREATE EXTENSION hstore` to the meta data migration, as that was missing when running postgres via postgres.app.