The changelog for an empty version will now be:
```
No user facing changes.
```
And this will appear in the final changelog when there is an actual release.
The benefits are that users will see regular release cycles and know
how old versions are even if there's no changes for a particular version
If we find that we are going months without any user facing changes, but
we have non-visible changes, then we can rethink this strategy.
But I think this is nicer than having empty sections for a version.
Adds an empty changelog file and a reminder to update it when opening
pull requests.
Also, adds a 1.0.0 version number in the package.json, which is what
we _could_ use for version numbering.
