server: Add zmq interface for publishing events

Change-Id: I383558bb9aad3cb149f35e13910a1d6aa79afc84
diff --git a/.travis.yml b/.travis.yml
index 13d630c..f602bfd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,6 +17,7 @@
       - libtalloc-dev
       - libpcsclite-dev
       - libpcap-dev
+      - libzmq3-dev
 
 script:
   - contrib/travis.sh