add docnetwork to list of users. (#654)

Signed-off-by: Matt McLane <mmclane@docnetwork.org>

Author: mmclane

data/users.yaml

@@ -25,6 +25,9 @@
 - title: de-cix
   logo: de-cix.png
   link: https://www.de-cix.net
+- title: DocNetwork
+  logo: docnetwork.png
+  link: https://docnetwork.org/
 - title: dynatrace
   logo: dynatrace-logo.png
   link: https://www.dynatrace.com/
@@ -60,4 +63,4 @@
   link: http://www.wise2c.com/
 - title: yanrongyun
   logo: yanrong-logo.png
-  link: https://www.yanrongyun.com/
+  link: https://www.yanrongyun.com/