Foreman Maintain

Fixes #22436: Fix some nitpicks

Fixes #21452 - Add yum clean all before packages update

Fixes #21070 - fix typos in documentation

[README] Add code-climate badge

Fixes #20751 - Add info for contributors in README.md

Fixes #20565 - Add license to the README.rst file

[README] Add travis-ci build status

Update README

Update from review

Advanced run command and tests

Configure repositories and update packages

Update readme

Fixes #44 - Change tag 'basic' to 'default'

Turn hammer feature into a utils class

After looking more into this, I think the util class is actually better
fit for the hammer case. I've also removed the detection of the
credentials from hammer configuration, as we actually don't need
the credentials by our own.

Make the spinner opt-in, not opt-out

The default spinner caused issues when one needs to interact with the
user (printing additional messages). As it's needed only for long
running actions, it should not be enforced by default.

Set next steps with the assert check

This allows adding more assertions to the check, each adding their own
next steps.

Allow running checks by label

Update readme

Update readme

Tests for runner and reporter

Update README

Basic gem structure