public Single<Gist> refreshGist(String id) {
        return gistService.getGist(id)
                .map(response -> addGist(response.body()));
    }
Refresh gist.

@param id The id of the Gist to update
@return refreshed gist
app/src/main/java/com/github/pockethub/android/core/gist/GistStore.java