Use `nightly` as the docker image tag for travis CI (#182)
* Use `nightly` as the docker image tag
* Update build.sh
diff --git a/tools/travis/build.sh b/tools/travis/build.sh
index 6e9107d..d4b1d1b 100755
--- a/tools/travis/build.sh
+++ b/tools/travis/build.sh
@@ -12,7 +12,7 @@
# Install OpenWhisk
cd $WHISKDIR/ansible
-ANSIBLE_CMD="ansible-playbook -i environments/local -e docker_image_prefix=openwhisk "
+ANSIBLE_CMD="ansible-playbook -i environments/local -e docker_image_prefix=openwhisk -e docker_image_tag=nightly"
$ANSIBLE_CMD setup.yml
$ANSIBLE_CMD prereq.yml