Upgrading from 0.x to 1.x

[treeder]

The only change is with stringify and handling HTML attribute objects.

• If you are using stringify explicitly, change to stringifyAttribute.
• If you are passing objects in as attributes, these will not be automatically stringified, you will have to call stringifyAttribute explicitly on them. Eg:

return html`<a myob="${stringifyAttribute(obj)}">`

[treeder]

This would be better once we implement something like #38