rust: Add a `ConfigValueParseError` variant to common errors Configuration files are parsed into sections of key/value pairs when they are read, but at that point values are still arbitrary bytes. Only when a value is accessed by various parts of the code do we know its expected type and syntax, so values are parsed at that point. Let?s make a new error type for this latter kind of parsing error, and add a variant to the common `HgError` so that most code can propagate it without much boilerplate. Differential Revision: https://phab.mercurial-scm.org/D10009

--- a/rust/hg-core/src/config.rs	Tue Feb 16 13:55:31 2021 +0100
+++ b/rust/hg-core/src/config.rs	Tue Feb 16 15:22:20 2021 +0100
@@ -11,5 +11,5 @@
 
 mod config;
 mod layer;
-pub use config::Config;
+pub use config::{Config, ConfigValueParseError};
 pub use layer::{ConfigError, ConfigParseError};