0.9.3

This release is available on PyPI: https://pypi.org/project/hardshare/
and the guide at https://hardshare.readthedocs.io/en/latest/index.html

Summary of changes:

• attach-camera: only upload video when there is active instance.
• To simplify creating misty-py sandboxes, adding or removing mistyproxy now does same for add-on py.