Replace travis with GitHub Actions (#497)

.github/workflows/lint.yml

@@ -0,0 +1,41 @@
+name: Lint
+on: [push, pull_request]
+
+jobs:
+  validate:
+    name: Validate
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    # - uses: actions/setup-ruby@v1
+    #   with:
+    #     ruby-version: '2.4.6'
+    # - name: Install Kitchen-Terraform
+    #   run: |
+    #     gem install bundler --no-document
+    #     bundle install
+    - name: Install Terraform
+      run: |
+        export TERRAFORM_VERSION=$(curl -s https://checkpoint-api.hashicorp.com/v1/check/terraform | jq -r -M '.current_version')
+        curl --silent --output terraform.zip "https://releases.hashicorp.com/terraform/${TERRAFORM_VERSION}/terraform_${TERRAFORM_VERSION}_linux_amd64.zip"
+        unzip terraform.zip ; rm -f terraform.zip; chmod +x terraform
+        mkdir -p ${HOME}/bin ; export PATH=${PATH}:${HOME}/bin; mv terraform ${HOME}/bin/
+        terraform -v
+    - name: Validate Code
+      env:
+        AWS_REGION: 'us-east-1'
+        TF_VAR_region: ${AWS_REGION}
+        TF_WARN_OUTPUT_ERRORS: 1
+      run: |
+        terraform init
+        terraform fmt -check=true
+        terraform validate -var "region=${AWS_REGION}" -var "vpc_id=vpc-123456" -var "subnets=[\"subnet-12345a\"]" -var "workers_ami_id=ami-123456" -var "cluster_ingress_cidrs=[]" -var "cluster_name=test_cluster"
+    - name: Validate Examples
+      run: |
+        for example in $(find examples -maxdepth 1 -mindepth 1 -type d); do
+          cd $example
+          terraform init
+          terraform fmt -check=true
+          terraform validate
+          cd -
+        done