- Add schema_migrations table to track applied migrations
- Migrate() now checks if a migration was already applied before running
- 0002 rewritten to use SAVEPOINT+ROLLBACK per column, making it safe
to run even if some columns were partially added previously
- Each migration runs in its own transaction; INSERT into schema_migrations
only happens if the SQL executes without error
- Bump VERSION 0.1.8 -> 0.1.9
darroyo