add get_doc_ids utility and tests
add initial userreports app with end to end filter tests
add factory, AND, OR filters, and tests
add test demonstrating ability to nest compound filters
make filters more generic, push logic to factory
add basic (boolean) indicator class and tests
DRYer spec validation
add choice list indicators and tests
add support and test for count indicator
add raw indicator format and simple test
add stub model to hold the config + simple test and sample config
make domain filter implicit in the indicator config class
add 1:1 mapping of indicator configs to doc_types

also make doc_type filtering handled in the code instead of config
switch filters and indicators to work off dicts and not Documents
flesh out config functionality, make config an indicator, expand tests
add "datatype" field to columns and raw indicators
add is_nullable and is_primary_key options to columns
split out config test into individual tests of functionality
add implicit doc_id column in indicator configs
allow is_nullable and is_primary_key to be set in the raw spec format