Initial release.

This is a trial release of the zeno package on GitHub. The present code is based on zeno.009e, which I put on my software website at the IfA on 20 May 2013. Since then I've made significant revisions to the code and adopted a new formatting style. I'm tagging this as version 0.10.0 to maintain continuity with the numbering on my website.

If this goes smoothly I will release version 0.10.0 as the final version on my website and continue development on GitHub in the future.