Fix a weird usage message of --context flag (#37)
Fix a weird usage message of --context flag (#37)

This commit fixes a weird usage message of --context flag.

```
--context string        Kubernetes context to use. Default to current context configured in kubeconfig.
```

/refs #36

Signed-off-by: Kazuki Suda <7503a71bc156cfc0db6c791efd79e4ef2a2ebf99@gmail.com>
wercker/stern,wercker/stern