wireproto: only expose "clonebundles" to version 1 transports This may make a comeback in wire protocol version 2. The feature definitely needs to be carried forward. But at this juncture, I'm flirting with the idea of implementing this via a "redirect" mechanism at the command response level itself rather than something that requires one-off client support for querying and handling. i.e. I want to make it so servers can say "fetch this first and then come back" and clients handle that automatically. This would not only support clone bundles, but would also support piece-meal "pull bundles." Whatever happens, we can deal with it down the road. Differential Revision: https://phab.mercurial-scm.org/D3203