Add build script to make git version available in code

Signed-off-by: pep <pep@bouah.net>

src/config.rs

@@ -23,6 +23,14 @@ use xmpp::jid::{BareJid, ResourcePart};
 
 use crate::error::Error;
 
+const MAYBE_VERSION: &'static str = include_str!(concat!(env!("OUT_DIR"), "/GIT_COMMIT"));
+const fn version() -> Option<&'static str> {
+	match MAYBE_VERSION {
+		v if v.is_empty() => None,
+		v => Some(v),
+	}
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
 	/// Accounts trusted for admin tasks
@@ -50,6 +58,11 @@ pub struct Config {
 	/// HTTP Webhook listening address and port, e.g., 127.0.0.1:1234 or [::1]:1234
 	#[serde(default = "Config::default_addr")]
 	pub addr: SocketAddr,
+
+	/// Software version
+	#[serde(skip)]
+	#[serde(default = "version")]
+	pub version: Option<&'static str>,
 }
 
 impl Config {