hghave: list the module needed for the `vcr` check I'm tired of having to look up modules each time I setup a system, and try to distinguish between similar package names to get the right one. Now that the search API has been disabled, it's even harder. There are other python packages here that should be listed like this, but this is the one that came up missing today, so it's a start. Differential Revision: https://phab.mercurial-scm.org/D9879

debugshell: add a simple command for starting an interactive shell This simplifies interactive exploration of the Mercurial APIs. The ui and repo instances are provided as local variables. Differential Revision: https://phab.mercurial-scm.org/D9866

rust: replace an unsafe use of transmute with a safe use of bytes-cast Differential Revision: https://phab.mercurial-scm.org/D9859

rust: use the bytes-cast crate to parse persistent nodemaps This crate casts pointers to custom structs, with compile-time safety checks, for easy and efficient binary data parsing. See https://crates.io/crates/bytes-cast and https://docs.rs/bytes-cast/0.1.0/bytes_cast/ Differential Revision: https://phab.mercurial-scm.org/D9788

cext: restore the ability to build on Windows with py2 This broke in e92ca942ddca. Differential Revision: https://phab.mercurial-scm.org/D9867

command-namespace: use `::` are the command separator This was discussed on the mailing list / phab and `::` got a couple of positive feedback. I dediced to not introduce automatic folding of `::`, I feel like it make sense for `-`, but I like the expliciteness of `::`. So I am adding alias for backward compatibility. Differential Revision: https://phab.mercurial-scm.org/D9872