Change loggin function to have f postfix when using formated version

[damtur]

Description

This change needs to go live with similar change to alyx3
It's using the newest format of logging from non-backward compatible update from op/go-logging package.

Backwards compatibility

Since github.com/op/go-logging did a breaking change we decided that we'll fix the code after upgreading that package. If you use old version of go-logging con't probably won't compile, but with newest version it should all be good
One should use Godep if is scared about that :(

Reasoning

• wanted newest feature of op/go-logging
• only one version of go-logging package for apps using fargo

Testing

This will affect mainly logs with formatting like %s. See if your logs looks ok after the change and are properly substituted

Dependency consideration

After reviewing dependent hudl repos this shouldn't affect anything as those which one are using fargo uses Godep as well. For outside of hudl world if someone is using hudl/fargo and not using Godep then probably they will have a problem with op/go-logging which this PR is fixing