rust-nodemap: building blocks for nodetree structures This is similar to `nodetreenode` in `revlog.c`. We give it a higher level feeling for ease of handling in Rust context and provide tools for tests and debugging. The encoding choice is dictated by our ultimate goal in this series, that is to make an append-only persistent version of `nodetree`: the 0th Block must be adressed from other Blocks. Differential Revision: https://phab.mercurial-scm.org/D7787

--- a/rust/hg-core/src/revlog.rs	Tue Jan 21 10:13:08 2020 -0500
+++ b/rust/hg-core/src/revlog.rs	Wed Jan 22 16:23:29 2020 +0100
@@ -5,6 +5,8 @@
 // GNU General Public License version 2 or any later version.
 //! Mercurial concepts for handling revision history
 
+pub mod nodemap;
+
 /// Mercurial revision numbers
 ///
 /// As noted in revlog.c, revision numbers are actually encoded in