add zmq for prime_server

Author: hjanetzek

.travis.yml

@@ -34,6 +34,10 @@ before_install:
     # - llvm-config --includedir
     # - llvm-config --libdir
     # - clang --version
+    - sudo add-apt-repository ppa:chris-lea/libsodium -y
+    - sudo add-apt-repository ppa:chris-lea/zeromq -y
+    - sudo apt-get update
+    - sudo apt-get install libsodium-dev libzmq5-dev -y
 
     - git submodule update --init
     - source ./scripts/travis/before_install.sh