Fix import bug

Author: loopj

src/com/loopj/android/http/AsyncHttpClient.java

@@ -39,6 +39,8 @@
 import org.apache.http.HttpResponse;
 import org.apache.http.HttpResponseInterceptor;
 import org.apache.http.HttpVersion;
+import org.apache.http.auth.AuthScope;
+import org.apache.http.auth.UsernamePasswordCredentials;
 import org.apache.http.client.CookieStore;
 import org.apache.http.client.HttpClient;
 import org.apache.http.client.methods.HttpDelete;