Update Configuration Documentation (#4258)
Update Configuration Documentation (#4258)

- Add section on array syntax
- Mark boolean syntax as legacy
palantir/tslint,mprobst/tslint,palantir/tslint,JoshuaKGoldberg/tslint,palantir/tslint,mprobst/tslint,JoshuaKGoldberg/tslint,mprobst/tslint,JoshuaKGoldberg/tslint