Return errors

[Davincible]

Hi, love your library. I just found out not all errors are returned, but instead handled by a func as here;

https://github.com/BoRuDar/configuration/blob/0bf51497fd0c0fc22938b4ac8f0d8e9aacd85cf9/configurator.go#L114

I found this quite strange behavior since the reset of the InitValues func does return errors. Would you be open to return all errors in InitValues directly?

I can make a PR