load migration files lazily, and ignore preceding numbering
improve docs and comments
change DbPump initialize to have all optional arguments
various batched result retrieval now Enumerates
better restore logging and sanity checking
better bz2 file opening
fix migration file numbering
Handle DbPump#db = nil, and improve quacks_like
use streaming if available (for postgres and mysql)
fix various broken comments in DbPump
fix numbering of schema migration files