travis: run e2e tests on master branch

Assumes the test cluster to be hosted in AWS. The following environment
variables need to be properly configured in the CI in order to
successfully run the tests:
AWS_ACCESS_KEY_ID
AWS_SECRET_ACCESS_KEY
AWS_REGION
KUBECONFIG_AWS

Also, the following are probably needed in order for the script to be be
able to push the container image to the remote registry:
IMAGE_REPO
IMAGE_REPO_PASSWORD
IMAGE_REPO_USER

.travis.yml

@@ -1,15 +1,28 @@
-language: minimal
+language: go
+go:
+  - "1.12"
 
 env:
   global:
     # Sanitize git branch name into a valid docker tag name
     - IMAGE_TAG_NAME=$(echo -n $TRAVIS_BRANCH | tr -c "[a-zA-Z0-9._'" "_")
+    - GO111MODULE=on
 
 services:
   - docker
 
 script:
   - make image -e
+  - if [ "$TRAVIS_BRANCH" == master -a -n "$IMAGE_REPO_USER" ]; then
+      set -e;
+      echo "$IMAGE_REPO_PASSWORD" | docker login -u "$IMAGE_REPO_USER" --password-stdin quay.io;
+      make push -e;
+      curl -o $HOME/bin/aws-iam-authenticator --create-dirs https://amazon-eks.s3-us-west-2.amazonaws.com/1.10.3/2018-07-26/bin/linux/amd64/aws-iam-authenticator;
+      chmod a+x $HOME/bin/aws-iam-authenticator;
+      export PATH=$PATH:$HOME/bin;
+      echo "$KUBECONFIG_AWS" > kubeconfig_aws;
+      make e2e-test -e KUBECONFIG=`pwd`/kubeconfig_aws;
+    fi
 
 deploy:
   - on: