Fixed copy/paste error in container_types table.
Chnaged serial in container_types to use a smallint sequence.
Added algorithms, users, and personas tables.
Added full list of relative rarities.
Renamed table set_cards to card_printings.
Removed note about using a BIGSERIAL for card printings.

The INT data type can have values over two billion, which should be enough to
keep track of all printings for a long time (there are less than 500k
printings in total now, I believe).
Added a multiverse_id column to card_printings.

The multiverse_id column will keep track of the multiverse id from the
Gatherer web site; this value is a unique id for all printings of all cards.
Removed note about a larger serial for card_card_types.
Commented out the card_card_types table definition.

As the 'todo' item discusses, I do not know if this table is needed.  If
anything, it is not needed initially, as it is not needed to simply keep track
of which cards were found in which boosters and containers.
Found a better name for this table.
Added todo item about formats.
Added missing semicolon.
Fixed order of precision and scale in numeric columns.
Moved card_types table definition after cards.
Commented out the card_types table.
Fixed spelling error in booster_packs reference.
Moved set_booster_images table to after card_printings.
Added card_printing_id column to set_booster_images.

The table set_booster_images, which tracks the images on each booster in each
set, should have a reference to the card_printings table to indicate which
card is being depicted on each booster instance.
Renamed table set_booster_images to booster_versions.
Added comment describing booster_versions table.