list filtered images as described in the remote api docs

This makes the `--filter` parameter work for the list images command. See https://docs.docker.com/reference/api/docker_remote_api_v1.15/#list-images for details.

The significant change is the renaming from `filter` to `filters`. A user has to provide the desired filters as json object, the encoding is performed transparently by the docker-java library. The `listDanglingImages` test should be a good example.

Attention: this is an api change!