tests: Attempt to set up nchan as part of unittests

.travis.yml

@@ -8,6 +8,9 @@ after_success:
 virtualenv:
   system_site_packages: true
 install:
+  - sudo add-apt-repository ppa:nginx/stable  -y
+  - sudo apt update
+  - sudo apt install libnginx-mod-nchan
   - echo "127.0.0.1 localhost" | sudo tee /etc/hosts
   - echo "127.0.1.1 ca.example.lan ca" | sudo tee -a /etc/hosts
   - echo "127.0.0.1 vpn.example.lan vpn" | sudo tee -a /etc/hosts
@@ -32,4 +35,5 @@ addons:
   hostname: ca
   apt:
     packages:
+    - software-properties-common
     - python-configparser