fixed falsy payload case

[vaukalak]

there could be some simple payloads like 0, '' or false, that will be skipped in current implementation. for that reason need to check against undefined.

[sergiodxa]

Hi @vaukalak

I'm the original author of the lib, since @PlatziDev is no longer maintaining this library I moved it back to my own account in https://github.com/sergiodxa/redux-duck.

I also solved this issue passing payload always to the action object, this way the property will be there always and you can decide to ignore it or use it based on what you know will be there.

This is published as the v1.1.0 of redux-duck in npm.