Appr

- Fixes [issues-23](https://github.com/app-registry/helm-plugin/issues/23)

- Integration with Helm's dependency file `requirements.yaml`
command: `helm dep`
- Allow push to any repository name,
it can be different from the application manifest
command: `push quay.io/ns/repo-name`
- Display server-error messages

- Upgrade appr-cli to 0.3.8
- No more registry-host default (localhost:5000)
- Pull command default to 'extract', use `--tarball` to keep the `tar.gz`