* Adds support for interating with Streams over interfaces that are tagged
with the x-dropshot-pagination extension. This requires clients to use
the futures crate.
Adds tests that compile generated clients.
Updates nexus.json to reflect a more recent omicron API.
Changes all generated methods to have a lifetime ('a) bound on all
references. This isn't necessary for most methods, but greatly
simplifies generation of the associated paginated interface.
Adam Leventhal