increase unit test coverage on config.go

[jodh-intel]

Currently very close to 100% (which looks to be achievable).

See #93.

[jodh-intel]

I think this just needs 1 more test similar to TestConfigLoadConfigurationFailBrokenSymLink() that creates a valid symlink to an unreadable file which will cause loadConfiguration() to fail.

[jodh-intel]

Hi @sboeuf - any update on this?

[sboeuf]

@jodh-intel this one is already all covered, isn't it ?

[jodh-intel]

Ah - I see what's happened - I raised this issue based on the coveralls output, but at that time coveralls was only running the tests as root. Now that #484 has landed, coveralls now gets to see the tests I actually wrote for config.go on #484 which increased the coverage to 100% when run as a non-root user!

Closing as already done 😄