Update hard-coded config example

src/command.rs

@@ -121,20 +121,9 @@ impl Updater {
     pub fn from_config(opt: &Opt) -> io::Result<Updater> {
         let mut updater = Updater::new();
 
+        // Example to generate a config file
         if false {
             updater.systems.push(System { packages: vec![] });
-            updater.systems[0].packages.push(Package {
-                name: "apt".to_owned(),
-                fetch: None,
-                compile: None,
-                install: Cmd {
-                    exe: "()".to_owned(),
-                    params: vec![],
-                    current_dir: None,
-                    env: HashMap::new(),
-                },
-                post_install: None,
-            });
 
             updater.systems[0].packages.push(Package {
                 name: "Rustup".to_owned(),
@@ -148,6 +137,20 @@ impl Updater {
                 },
                 post_install: None,
             });
+
+            updater.systems[0].packages.push(Package {
+                name: "Cargo".to_owned(),
+                fetch: None,
+                compile: None,
+                install: Cmd {
+                    exe: "cargo".to_owned(),
+                    params: vec!["install-update".to_owned(), "-a".to_owned()],
+                    current_dir: None,
+                    env: HashMap::new(),
+                },
+                post_install: None,
+            });
+
             updater.write_config(opt);
 
             panic!("Wrote a config sample.");