build: only sign if a gpg key able to sign is present

src/lib.rs

@@ -17,6 +17,9 @@ pub mod pull;
 /// Handle context for .deb building: locally, over ssh, in a chroot...
 pub mod context;
 
+/// Utility functions
+pub(crate) mod utils;
+
 /// Optional callback function (taking 4 arguments)
 /// - Name of the current main operation (e.g. pulling package)
 /// - Name of the current nested operation (e.g. cloning git repo)