No way to `text-shadow: none`

[nsaunders]

After reviewing the CSS.Text.Shadow module, I don't see how it would be possible to create a declaration equivalent to text-shadow: none (initial, inherit, ...) If anyone is aware of something I've overlooked, please let me know.

Possible solutions:

1. textShadow as a polyvariadic function
2. Specialized functions like textShadowNone