Update readme: drop broken coverage and CI badges (#40)

drop broken coverage and CI badges
diff --git a/README.md b/README.md
index 0487c5c..44932a6 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,3 @@
-# Platform
-
-[![Build Status -](https://travis-ci.org/google/platform.dart.svg?branch=master)](https://travis-ci.org/google/platform.dart)
-[![Coverage Status -](https://coveralls.io/repos/github/google/platform.dart/badge.svg?branch=master)](https://coveralls.io/github/google/platform.dart?branch=master)
 [![Pub](https://img.shields.io/pub/v/platform.svg)](https://pub.dartlang.org/packages/platform)
 
 A generic platform abstraction for Dart.