What I was doing in my branch was wrapping every argument as a function, then when gettext.js does its thing, it tries invokes each argument before using it. That means things it doesn't care about won't get looked at, and things it does care about will have an error thrown. Since gettext.js should be generic (so it can be usable when extracting from other things, ie #11), I was changing gettext.js to offer a parse option.

I'd be happy to move those changes into this PR and re-use the identifier detection that @JSteunou has done here, if you guys are happy with that?