Plugin: restore documentation path on page/schema reload

At the moment, reloading the page is the only way to reload changes to the schema/documentation of said schema.
It is fine in production, since schema will not change every second, and mostly fine in development (of a GraphQL endpoint) because the state is mostly kept.

However, the documentation resets, which means I either have to click the correct sequence of types, or use the search field, every time I refresh the page.

I think it would be very intuitive to reload the documentation as it was before refreshing the page. This could be done via a `?documentation=...` query string (in addition of `?query=...`). Any thoughts? :)