/!\ NOT UPSTREAM: two-step: Hack to allow promptless / messageless boots

We don't have enough time to implement entries in our boot, and our
customers won't want them, so just hack the two-step plugin so that
we don't need them to load a theme.
Merge pull request #1 from endlessm/shell/3769

/!\ NOT UPSTREAM: two-step: Hack to allow promptless / messageless boots