Why not add useCss to this library?

[scottmas]

This library has 95% of the functionality in the useCss hook but isn't itself made available in this library. I would prefer to add just nano-css rather than react-use since the dependency tree for that package is pretty large. Obviously it's not too crazy to just add the useCss code directly to my project but it would be nice to just include it directly from this package. Thanks for the nice work on this package!