updated ansible version for travis/setup.sh (#295)

diff --git a/tools/travis/setup.sh b/tools/travis/setup.sh
index 173853e..1358ef1 100755
--- a/tools/travis/setup.sh
+++ b/tools/travis/setup.sh
@@ -36,7 +36,7 @@
 pip install --user couchdb
 
 # Ansible
-pip install --user ansible==2.4.2.0
+pip install --user ansible==2.5.0
 
 # jshint support
 sudo apt-get -y install nodejs npm