update readme

README.md

@@ -69,7 +69,7 @@ After installing the module through NPM, the API wrapper can be used as detailed
 
 ```js
 const gitrest = require('git-rest-wrapper');
-const provider = new gitrest.RequestProvider();
+const provider = new gitrest.Client();
 
 provider.getUser("fennifith").then((user) => console.log(user.name));
 ```
@@ -77,7 +77,7 @@ provider.getUser("fennifith").then((user) => console.log(user.name));
 The bundled JS file works the same as the NPM module - except the `gitrest` object will be available in the global scope.
 
 ```js
-const provider = new gitrest.RequestProvider();
+const provider = new gitrest.Client();
 
 provider.getUser("fennifith").then((user) => console.log(user.name));
 ```