InteractiveAuthEntryComponents is not a single component and
doesn't really fit into the structure: ignore it, otherwise
we crash when loading the skin.
We are now using `cpx` to copy the emojione files, so we might as well use it
for olm.js, rather than rolling our own - particularly since that makes it easy
to add a watcher for `npm start`.
We have to add a `-L` to the `cpx` invocation, otherwise, if olm is a
symlink (as is useful for development), cpx ends up watching the symlink, which
obviously never changes.
