add withCredentials to the configuration (#5484)

* add withCredentials to the configuration

1. `withCredentials` in Request is `false` default
2. if want to set the `withCredentials` as `true` (for CORS request),
 instance `Configuration` object and set the `withCredentials` as `true`.

* simplify the code according to the code review

modules/swagger-codegen/src/main/resources/typescript-angular2/api.mustache

@@ -205,9 +205,8 @@ export class {{classname}} {
             body: formParams.toString(),
 {{/hasFormParams}}
             search: queryParameters,
-            withCredentials:true
+            withCredentials:this.configuration.withCredentials
         });
-
         // https://github.com/swagger-api/swagger-codegen/issues/4037
         if (extraHttpRequestParams) {
             requestOptions = (<any>Object).assign(requestOptions, extraHttpRequestParams);

modules/swagger-codegen/src/main/resources/typescript-angular2/configuration.mustache

@@ -3,4 +3,5 @@ export class Configuration {
     username: string;
     password: string;
     accessToken: string | (() => string);
+    withCredentials: boolean;
 }