Migrate to GitHub workflows for CI

.github/workflows/ci.yml

@@ -0,0 +1,46 @@
+name: krew-index CI
+
+on:
+- push
+- pull_request
+
+jobs:
+  build:
+    name: Build and Tags
+    runs-on: ubuntu-latest
+    env: 
+      KREW_VERSION: v0.3.3
+      GO111MODULE: on
+    steps:
+
+    - name: Check out code into the Go module directory
+      uses: actions/checkout@v1
+
+    - name: Install kubectl
+      run: |
+        set -euo pipefail
+        sudo curl -fsSL -o /usr/bin/kubectl https://storage.googleapis.com/kubernetes-release/release/v1.13.1/bin/linux/amd64/kubectl
+        sudo chmod +x /usr/bin/kubectl        
+
+    - name: Install krew
+      shell: bash
+      run: |
+        set -euo pipefail
+        cd "$(mktemp -d)" &&
+        curl -fsSLO "https://github.com/kubernetes-sigs/krew/releases/download/${KREW_VERSION}/krew.{tar.gz,yaml}" &&
+        tar zxvf krew.tar.gz &&
+        ./krew-linux_amd64 install --manifest=krew.yaml --archive=krew.tar.gz
+
+    - name: Install validate-krew-manifest plugin
+      run : |
+        set -euo pipefail
+        export GOBIN=$HOME/bin
+        go get sigs.k8s.io/krew/cmd/validate-krew-manifest@${KREW_VERSION}
+
+    - name: Validate updated plugin manifests
+      run : |
+        set -euo pipefail
+        export PATH="${KREW_ROOT:-$HOME/.krew}/bin:$PATH"
+        git diff --name-only --diff-filter=AM ${{ github.event.before }} ${{ github.sha }} |
+          grep -E 'plugins/.*' | tee /dev/stderr |
+          xargs -I _ $HOME/bin/validate-krew-manifest -manifest _

plugins/whoami.yaml

@@ -36,4 +36,3 @@ spec:
       https://github.com/rajatjindal/kubectl-whoami
   description: |
     This plugin show the subject that's currently authenticated as.
-