add new Cargo.lock file to make builds reproducable

Author: Sven Lechner

.gitignore

@@ -23,7 +23,7 @@ tags
 
 # Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
 # More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
-Cargo.lock
+#Cargo.lock
 
 # These are backup files generated by rustfmt
 **/*.rs.bk