Update README.md

Author: mariobehling

README.md

@@ -9,6 +9,8 @@
 [![codecov](https://codecov.io/gh/fossasia/open-event-frontend/branch/development/graph/badge.svg)](https://codecov.io/gh/fossasia/open-event-frontend)
 [![Known Vulnerabilities](https://snyk.io/test/github/fossasia/open-event-frontend/badge.svg)](https://snyk.io/test/github/fossasia/open-event-frontend)
 [![Crowdin](https://d322cqt584bo4o.cloudfront.net/open-event-frontend/localized.svg)](http://translate.eventyay.com/project/open-event-frontend)
+[![Mailing List](https://img.shields.io/badge/Mailing%20List-FOSSASIA-blue.svg)](https://groups.google.com/forum/#!forum/open-event)
+[![Twitter Follow](https://img.shields.io/twitter/follow/eventyay.svg?style=social&label=Follow&maxAge=2592000?style=flat-square)](https://twitter.com/eventyay)
 
 The front end for the **Open Event Server**