The taglib has move to context-client-taglib.jar, which is in Content Delivery/roles/context/extension-web/java/lib.
As far as I know, you only need the following dependencies, apart from core CIL, including OData:
- context-service-common-8.5.0-*.jar
- context-api-8.5.0-*.jar
- context-client-8.5.0-*.jar