rock: add datasets -- roster_2004.csv, game_log_2004.csv, statlines

[BryanChasko]

rock

populate the datasets/ directory with real 2004 patriots data.
all examples stub out or read from these files -- they need to ship.

files to create

• datasets/roster_2004.csv -- 53-man roster: name, number, position, years_with_patriots
• datasets/game_log_2004.csv -- week, opponent, location, pts_for, pts_against, result
• datasets/receiving_stats_2004.csv -- name, receptions, targets, yards, tds, yards_per_rec
• datasets/rushing_stats_2004.csv -- name, attempts, yards, tds, yards_per_attempt
• datasets/brady_by_game_2004.csv -- week, opponent, comp, att, yards, tds, ints, rating

source

use publicly available nfl box score data. add attribution comment row in each file.
same data source as the python sister repo datasets/ where possible.

why this matters

without real data, the file_io, regex, concurrency, and iterators examples
are incomplete. datasets ship before those modules do.