Clean up the data file
Add route-to-shape map file
Add code to draw a map of late night ridership data

Features include
- Rapid transit lines with brightness proportional to ridership
- Bus lines
- Rapid transit stations (which are not showing up so well)

Dependencies include:
- a shapes.txt file from the MBTA
- a shapes-by-route.txt file
- sqlite3 version of the ridership data
- cairo for the drawing
Add some data files needed for map code
Add sqlite version of ridership data
Fix drawing of stations

"map" objects can only be iterated once. Who knew.
Draw Silver Line Washington St (as bus routes).

Also fix Red Line color and clean up some extraneous print statements.
Remove dead code and comments
Move data-fetching code into a separate mapdata.py file.
Draw Silver Line subway and its stations
Add a clock
Put (filtered) shapes.txt into git

This file is based on the MBTA's GTFS data.
Add a wrapper shell script to run all the steps

- Run the main drawmap.py
- convert all the pngs to gifs (quantizing to 256 colors on the way)
- use gifsicle to make an animated gif
Include SL/Green Line surface data in line totals.
Make the map bigger
Move clock code to its own file.

It really stands pretty much alone.
Add drawing of subway-surface lines

This includes the Green branches, Silver Line SL1 and SL2, and
the Mattapan line.
Includes a hack to draw only the subway parts of the Green Line
as a subway line (leaving the rest to be drawn as subway-surface).
Make map size configurable