small error within an example in README.md

[momolinus]

Hello,

here
https://github.com/TNG/config-builder#usage-example
the class StringToPidFixTransformer implements TypeTransformer

public static class StringToPidFixTransformer implements TypeTransformer<String,PidFix>

but I think it should be extends

public static class StringToPidFixTransformer extends TypeTransformer<String,PidFix>

I'm right?

thank you for your tool - I like it!

[wuan]

thanks!