Fix README

Author: sfackler

README.md

@@ -10,23 +10,22 @@ r2d2-postgres
 # Example
 
 ```rust
-extern crate r2d2;
-extern crate r2d2_postgres;
-extern crate postgres;
-
 use std::thread;
-use r2d2_postgres::{TlsMode, PostgresConnectionManager};
+use postgres::{NoTls, Client};
+use r2d2_postgres::PostgresConnectionManager;
 
 fn main() {
-    let manager = PostgresConnectionManager::new("postgres://postgres@localhost",
-                                                 TlsMode::None).unwrap();
+    let manager = PostgresConnectionManager::new(
+        "host=localhost user=postgres".parse().unwrap(),
+        NoTls,
+    );
     let pool = r2d2::Pool::new(manager).unwrap();
 
     for i in 0..10i32 {
         let pool = pool.clone();
         thread::spawn(move || {
-            let conn = pool.get().unwrap();
-            conn.execute("INSERT INTO foo (bar) VALUES ($1)", &[&i]).unwrap();
+            let mut client = pool.get().unwrap();
+            client.execute("INSERT INTO foo (bar) VALUES ($1)", &[&i]).unwrap();
         });
     }
 }