docs(readme): add Greenkeeper badge

greenkeeper[bot] · greenkeeper[bot] · commit 54bd87c4199c · 2018-02-05T07:41:16.000Z
diff --git a/README.md b/README.md
@@ -0,0 +1,3 @@
+
+
+[![Greenkeeper badge](https://badges.greenkeeper.io/emailjs/emailjs-base64.svg)](https://greenkeeper.io/)

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	`1`	`+`
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	`3`	`+[![Greenkeeper badge](https://badges.greenkeeper.io/emailjs/emailjs-base64.svg)](https://greenkeeper.io/)`