version bumps of hammer_cli and foreman_api

also no longer requiring `mime-types` because that's already required by
hammer-cli

- [ ] this pull-request first requires that theforeman/hammer-cli#74 be merged
with a new gem version released.

- [ ] this pull-request first requires that theforeman/foreman_api#23 be
merged with a new gem version released.

after the above gems are built, hopefully will build and release a new version `0.0.17` for `hammer_cli_katello` to consume.