Add python3.5-dev package to travis

Change-Id: Iaa1222f487972c99255fffe087fd16d56f54933c

Author: Jon Wayne Parrott

.travis.yml

@@ -24,6 +24,7 @@ addons:
     packages:
     - portaudio19-dev
     - python3.5
+    - python3.5-dev
 install:
 - pip install --upgrade pip wheel virtualenv
 - pip install nox-automation coverage