chore: add refs

examples/crowdsec/README.md

@@ -1,4 +1,7 @@
 # References
+- https://github.com/crowdsecurity/crowdsec
+- https://github.com/maxlerebourg/crowdsec-bouncer-traefik-plugin
+- https://app.crowdsec.net/hub/collections
 - https://www.reddit.com/r/selfhosted/comments/1dcn19v/standing_up_the_crowdsec_bouncer_plugin_in_traefik/
 
 # Notes