Add beginning of a script to create a cleaned data table.

The script is a hack at the moment.
Simplify query logic by precomputing polls to merge
Add computation for electors and nonvoters.
Rename add_votes to add_to_column
Rename fednum to fed_num to be consistent with shapefile tables
add poll names
commit transaction in process_poll
add a function that maps process_poll over shapefile data
Fix bug in poll search query
reduce size of table fields