nano.request() missing type in nano.d.ts

According to documentation of nano.request opts.stream is supported and Request object is returned instead of Promise, but in nano.d.ts this is not the case.

Open nano.d.ts and compare the nano.request declaration with the linked nano.request documentation, focusing on opts.stream and the returned value. Update the type definition so the documented behavior is represented, then verify that the declaration matches both request modes.

Written by the indexing model from the issue text.