add comment and move intercepter to client packege

lib/client/app_client.dart

@@ -1,6 +1,10 @@
 import 'package:doctor_app_flutter/interceptor/http_interceptor.dart';
 import 'package:http/http.dart';
 
+// OWNER : Ibrahim albitar
+// DATE : 22-04-2020
+// DESCRIPTION : Custom App client to pin base url for all srvices 
+
 class AppClient {
   static const String BASE_URL = "https://hmgwebservices.com/";