Release of refactored version 1.0 for the extension.

This will mark the release of a stable long term version of the extension which will tie in with a re-write of the underlying code-base for better long term maintenance and reliability.

1. refactor translators to specialise on ipynb, html, pdf to improve maintainability
2. use more of sphinx infrastructure for management of static assets
3. revisit dask futures execution model to handle more tasks heterogenously.