Merge pull request #7613 from metabase/distribution-drill

frontend/src/metabase-lib/lib/Question.js

frontend/src/metabase/lib/schema_metadata.js

frontend/src/metabase/meta/Card.js

...nd/src/metabase/qb/components/drill/DistributionDrill.jsx

...etabase/qb/components/drill/SummarizeColumnByTimeDrill.js

.../src/metabase/qb/components/drill/SummarizeColumnDrill.js

frontend/src/metabase/qb/components/modes/SegmentMode.jsx

frontend/src/metabase/qb/lib/actions.js

frontend/src/metabase/query_builder/actions.js

...nd/src/metabase/query_builder/containers/QueryBuilder.jsx

frontend/src/metabase/query_builder/reducers.js

frontend/src/metabase/query_builder/selectors.js

.../metabase/visualizations/components/ChartClickActions.jsx

frontend/test/metabase-bootstrap.js

frontend/test/modes/drills/CountByColumnDrill.integ.spec.js

frontend/test/modes/drills/CountByColumnDrill.unit.spec.js

...test/modes/drills/SummarizeColumnByTimeDrill.unit.spec.js

src/metabase/types.clj