Prefer CLI config over Knife config for locate_config_value

[shortdudey123]

@martinb3 @tas50 can you guys review and let me know if you have any feedback? thanks!

[martinb3]

I was concerned that config might contain a default option that we'd pick over a config file setting -- would you mind adding a test for something that has a default value, like flavor? Just to be sure we don't pick a default over a config file option?

[shortdudey123]

@martinb3 working on trying to get a correct test

FWIW... this is the same think knife-ec2 has https://github.com/chef/knife-ec2/blob/master/lib/chef/knife/ec2_base.rb#L104

[martinb3]

@shortdudey123 that's a fair point. I'll go ahead and merge and if you get a good test, feel free to open as a new PR.

[shortdudey123]

awesome, thanks!