Add frontend as submodule; Update README.md

.github/workflows/test.yml

@@ -0,0 +1,17 @@
+name: Build & Test
+on: [push, pull_request]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.16.x
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Build, Vet & Test
+        run: |
+          go build ./...
+          go vet ./...
+          go test -v ./...