Make a 0.4.6 release

[davidcassany]

Since march 2017 that there isn't any new release. Even I am aware there haven't been many commits since then and that most of them are documentation related I think it makes sense to release a new version. For packaging at openSUSE we'l love to see a new version including the latest commits including the LICENSE and AUTHORS in the sdist tarball (8102baf). This way we can easily package that without having to manually look for the license and append it.

Bumping the patch version is also expected to be a simple update without new features, I think it would make sense.

[davidcassany]

@jplana gentle ping. What you think about it, is it feasible to make to tag a new release to include the above mentioned commit? Thanks

[rliu054]

@jplana gentle ping again, can we please make a new release? The last release was a few years ago. Thank you.