merge with default to begin 4.6 freeze # no-check-commit because of many vendored packages

rebase: introduce support for automatically rebasing orphan changes _destautorebase(SRC) is based on the _destrestack(SRC) revset from fbamend. The supporting _possibledestination function is extracted from evolve, with minor cleanups. We've considered some alternatives here: * This change, but with --auto as the flag name. We're hedging our bets on this a little in this change so that if this ends up being the wrong direction we haven't burned the valauble --auto name on rebase. * --destination auto: I've got reservations about the discoverability of this, and we don't currently have a good story for a revset alias of sorts that changes behavior depending on the context in which it's used. * A "rebase presets" feature, where we could use the currently-an-error positional argument space for the rebase command to define presets, so that users could define a 'linearize' preset that specifies --revision='orphan()-obsolete()' and --dest=_destautoorphanrebase(SRC). Personally, I find the third option somewhat appealing, but am hesitant to "spend" the functionality space of positional arguments to the rebase command. We should revisit the way we expose this functionality sometime in the 4.7 cycle once we've had a chance to vet the implementation of the functionality. Differential Revision: https://phab.mercurial-scm.org/D2668

py3: whitelist six new passing tests Differential Revision: https://phab.mercurial-scm.org/D3406

wireproto: rename wireproto to wireprotov1server (API) We have wireprotov2server, wireprotov1peer, and wireprotov2peer. wireproto only contains server functionality. So it makes sense to rename it to wireprotov1server so the naming aligns with everything else. Differential Revision: https://phab.mercurial-scm.org/D3400

wireproto: move version 2 commands dict to wireprotov2server This was the final piece of version 2 referenced in wireproto. The break between server implementations is now much cleaner. Differential Revision: https://phab.mercurial-scm.org/D3399

wireproto: move supportedcompengines out of wireproto This function is used by both version 1 and version 2. It belongs in a common module. "wireprototypes" may not be the best module name. I may rename it... Differential Revision: https://phab.mercurial-scm.org/D3398

wireproto: reimplement dispatch() for version 2 server The code is minimal. I'm trying to create a cleaner break between version 1 and version 2 server code. Differential Revision: https://phab.mercurial-scm.org/D3397

wireproto: move command registration types to wireprototypes These are shared across wire protocol implementations. wireprototypes is our module for common code. Differential Revision: https://phab.mercurial-scm.org/D3396

wireproto: make version 2 @wireprotocommand an independent function Previously, the code for this decorator was shared between version 1 and version 2 commands. Very few parts of the function were identical. So I don't think sharing is justified. wireprotov2server now has its own @wireprotocommand decorator function. Because the decorator is no longer shared, code for configuring the transport policy has been removed. i.e. commands must have separate implementations for each wire protocol version. Differential Revision: https://phab.mercurial-scm.org/D3395

wireproto: don't pass transportpolicy argument The default is version 1 only. So we don't need to pass this argument when declaring commands. Differential Revision: https://phab.mercurial-scm.org/D3394