Start re-architecturing how events are parsed

Many of the functions to handle events are beginning to look similar.
Instead of adding more functions to reduce duplicate code, merge things
as much as possible into a single function. This will also reduce the
number of functions, hopefully improving speed.
Copy contents of simple into summarize_years_games
Use list instead of dict

Use a list instead of dict for separating offense from defense. It's
more opaque, but should be marginally faster.
Alias the batter to 'base0'

This makes it simpler to do some baserunning loops.
Start recording things

Greatly reduced accounting, but it's a start.
Track offensive stats

Next, defensive stats
Track base running stats: SB, CS, and PO
Delete simple function

No longer needed.
Track some pitcher stats
Don't count SB, CS, and PO for the batter

Was accidentally counting base-running stats for the batter.