add a bench

Author: jinmingjian

examples/simple_bench.rs

@@ -0,0 +1,13 @@
+use log::*;
+use baselog::*;
+
+use std::fs::File;
+
+fn main() {
+    CombinedLogger::init(vec![
+        TestLogger::new(LevelFilter::Info, Config::default()),
+    ])
+    .unwrap();
+    
+    info!("This only appears in the log file");
+}