Allow hash selector as last argument to property

[elhil]

Small API improvement idea: instead of

stuff({ css: 'div.some-class' }, :list)

I want to be able to write:

stuff :list, css: 'div.some-class'

To me, this reads more like idiomatic ruby.

For the edge case where a user specifies both positional and hash arguments, we could just accept the first one? Or merge the two?

If you think this is worth it, I'd be happy to make a PR 😄