Initial commit of management commands for ideology app

This set of commands will handle loading raw data into the database,
creating summary statistics of ideology for individual Congresses,
and other boring management tasks we want to automate.
Changed name of party_code to id, added district and chamber fields
Fixed some column/comma issues
Changed name of party_code to party_id, added district and chamber fields
Management command to load ideology data into database via `manage.py
load_ideology`