wireproto: allow direct stream processing for unbundle Introduce a new option server.streamunbundle which starts a transaction immediately to apply a bundle instead of writing it to a temporary file first. This side steps the need for a large tmp directory at the cost of preventing concurrent pushes. This is a reasonable trade-off for many setups as concurrent pushes for the main branch at least are disallowed anyway. The option defaults to off to preserve existing behavior. Change the wireproto interface to provide a generator for reading the payload and make callers responsible for consuming all data. Differential Revision: https://phab.mercurial-scm.org/D2470