modifiing grammar for instructions in file

src/main.rs

@@ -1,8 +1,11 @@
+use reactionsystems::rsprocess::presets;
+
 fn main() {
     // let now = std::time::Instant::now();
     // println!("{}", now.elapsed().as_micros());
 
-    let (g, t) = reactionsystems::rsprocess::presets::digraph("testing/first.system".into()).unwrap();
-
-    reactionsystems::rsprocess::presets::dot(&g, &t, "testing/first.dot".into()).unwrap();
+    match presets::run("testing/first.system".into()) {
+	Ok(_) => {},
+	Err(e) => {println!("{e}")}
+    }
 }