Pass Query Options to Content

[thombruce]

We should at least be able to pass a where() query to $content via $taxonomies. For my own purposes, this will allow me to filter out tags belonging only to documents still having draft: true... but it needs to be more general, because that's pretty opinionated and specific to my needs.

We do expose .$content from $taxonomies - perhaps that could be worked with.

Alternatively, an additional argument could be passed to $taxonomies for contentQuery or something like that.