テストに失敗する

```
00:16:08.153 Failures:
00:16:08.153 
00:16:08.154   1) File "/home/kazu634/.ssh/config" should match md5checksum "909715fcdbea44560c38f6d08b74038b"
00:16:08.155      Failure/Error: it { should match_md5checksum '909715fcdbea44560c38f6d08b74038b' }
00:16:08.159        sudo md5sum /home/kazu634/.ssh/config | grep -iw -- \^909715fcdbea44560c38f6d08b74038b
00:16:08.159        
00:16:08.160        expected File "/home/kazu634/.ssh/config" to match md5checksum "909715fcdbea44560c38f6d08b74038b"
00:16:08.161      # ./spec/kazu634/ssh_spec.rb:34:in `block (2 levels) in <top (required)>'
00:16:08.161 
00:16:08.162 Finished in 12.03 seconds
```

This issue refs #56.