[readme] Add Travis-CI and Coveralls badges for master branch

Author: Maks3w

README.md

@@ -1,5 +1,8 @@
 # zend-servicemanager
 
+[![Build Status](https://secure.travis-ci.org/zendframework/zend-servicemanager.svg?branch=master)](https://secure.travis-ci.org/zendframework/zend-servicemanager)
+[![Coverage Status](https://coveralls.io/repos/zendframework/zend-servicemanager/badge.svg?branch=master)](https://coveralls.io/r/zendframework/zend-servicemanager)
+
 The Service Locator design pattern is implemented by the `Zend\ServiceManager`
 component. The Service Locator is a service/object locator, tasked with
 retrieving other objects.