Update readme/example to rmeove webpki-roots mention

Author: ctz

README.md

@@ -8,8 +8,8 @@ and the [hyper HTTP library](https://github.com/hyperium/hyper).
 
 [API Documentation](https://docs.rs/hyper-rustls/)
 
-By default clients verify certificates using the `webpki-roots` crate, which includes
-the Mozilla root CAs.
+By default clients verify certificates using the `rustls-native-certs` crate, which uses
+the platform's root CAs.
 
 # License
 hyper-rustls is distributed under the following three licenses:

examples/client.rs

@@ -37,7 +37,7 @@ fn run_client() -> io::Result<()> {
         }
     };
 
-    // Second parameter is custom Root-CA store (optional, defaults to webpki).
+    // Second parameter is custom Root-CA store (optional, defaults to native cert store).
     let mut ca = match env::args().nth(2) {
         Some(ref path) => {
             let f = fs::File::open(path)