Modify CI badge (#29)

Author: yu-iskw

README.md

@@ -1,9 +1,9 @@
-# `bigquery-to-datastore`
+# bigquery-to-datastore
 
-[![Build Status](https://travis-ci.org/yu-iskw/bigquery-to-datastore.svg?branch=master)](https://travis-ci.org/yu-iskw/bigquery-to-datastore)
+[![CircleCI](https://circleci.com/gh/yu-iskw/bigquery-to-datastore.svg?style=svg)](https://circleci.com/gh/yu-iskw/bigquery-to-datastore)
 [![codecov](https://codecov.io/gh/yu-iskw/bigquery-to-datastore/branch/master/graph/badge.svg)](https://codecov.io/gh/yu-iskw/bigquery-to-datastore)
 
-This allows us to export a BigQuery table to a Google Datastore kind using Apache Beam on top of Google Dataflow.
+This enables us to export a BigQuery table to a Google Datastore kind using Apache Beam on top of Google Dataflow.
 
 You don't have to have duplicated rows whose key values are same.
 Apache Beam's `DatastoreIO` doesn't allow us to write same key at once.