Merge branch 'master' of github.com:metabase/metabase into new-e2e-test-setup

docs/contributing.md

frontend/src/metabase/dashboard/selectors.js

frontend/src/metabase/home/components/Activity.jsx

frontend/src/metabase/meta/Dashboard.js

frontend/src/metabase/meta/metadata/Field.js

src/metabase/db/migrations.clj

src/metabase/driver/generic_sql.clj

src/metabase/models/field.clj

test/metabase/driver/postgres_test.clj