Add ReactJS Girls Conference to Conference List (#1762)

- add upcoming ReactJS Girls Conf 
- move past conferences to the right place

content/community/conferences.md

@@ -12,10 +12,6 @@ Do you know of a local React.js conference? Add it here! (Please keep the list c
 
 ## Upcoming Conferences {#upcoming-conferences}
 
-### React Iran 2019 {#react-iran-2019}
-January 31, 2019 in Tehran, Iran
-[Website](http://reactiran.com) - [Instagram](https://www.instagram.com/reactiran/)
-
 ### Reactathon 2019 {#reactathon-2019}
 March 30-31, 2019 in San Francisco, USA
 
@@ -31,6 +27,11 @@ April 12, 2019 in Amsterdam, The Netherlands
 
 [Website](https://react.amsterdam) - [Twitter](https://twitter.com/reactamsterdam) - [Facebook](https://www.facebook.com/reactamsterdam)
 
+### ReactJS Girls Conference 
+May 3, 2019 in London, UK
+
+[Website](https://reactjsgirls.com/) - [Twitter](https://twitter.com/reactjsgirls)
+
 ### ReactEurope 2019 {#reacteurope-2019}
 May 23-24, 2019 in Paris, France
 
@@ -343,3 +344,8 @@ November 4 in Tel Aviv, Israel
 November 30, Berlin, Germany
 
 [Website](https://reactday.berlin) - [Twitter](https://twitter.com/reactdayberlin) - [Facebook](https://www.facebook.com/reactdayberlin/) - [Videos](https://www.youtube.com/channel/UC1EYHmQYBUJjkmL6OtK4rlw)
+
+### React Iran 2019 {#react-iran-2019}
+January 31, 2019 in Tehran, Iran
+
+[Website](http://reactiran.com) - [Instagram](https://www.instagram.com/reactiran/)