removed obsolete import statements from various files. removed the obsolete graph_filter.py. moved many methods from their old files to more logical destinations. data_helper.py is a new file containing only methods which access static measurement files. database_helper.py now only contains methods that still access the DB, either via psycopg2 or the django querying API. views.py only contains methods which return an HTML object and are called from urls. geoip_helper.py contains only methods which utlize the geoip API