Fixed csvexport to write in primary key order.

Good news: This no longer relies on InnoDB's default row order.

Bad news: InnoDB in MySQL 5.0 has a bug where it will sort rows
physically according to a secondary index, if there's a composite
primary key and a single-column index and the phase of the moon is
right.  So a couple tables have been, once again, reordered -- but
correctly this time.

Good news: This bug will no longer fuck me up!

pokedex/__init__.py

@@ -142,7 +142,8 @@ def command_csvexport(engine_uri, directory='.'):
         columns = [col.name for col in table.columns]
         writer.writerow(columns)
 
-        for row in session.query(table).all():
+        primary_key = table.primary_key
+        for row in session.query(table).order_by(*primary_key).all():
             csvs = []
             for col in columns:
                 # Convert Pythony values to something more universal