Add React Barcamp Cologne 2020 to Conferences (#2594)

* Add React Barcamp Cologne 2020 to Conferences

* Update conferences.md


Co-authored-by: Alexey Pyltsyn <lex61rus@gmail.com>

content/community/conferences.md

@@ -22,6 +22,11 @@ December 6, 2019 in Berlin, Germany
 
 [Website](https://reactday.berlin) - [Twitter](https://twitter.com/reactdayberlin) - [Facebook](https://www.facebook.com/reactdayberlin/) - [Videos](https://www.youtube.com/reactdayberlin)
 
+### React Barcamp Cologne 2020 {#react-barcamp-cologne-2020}
+February 1-2, 2020 in Cologne, Germany
+
+[Website](https://react-barcamp.de/) - [Twitter](https://twitter.com/ReactBarcamp) - [Facebook](https://www.facebook.com/reactbarcamp)
+
 ### ReactConf AU 2020 {#reactconfau}
 February 27 & 28, 2020 in Sydney, Australia