Migrate the CI from travis-ci to Github Actions

Because travis-ci.org will be shutting down.

Signed-off-by: Tim Zhang <tim@hyper.sh>

.github/workflows/bvt.yaml

@@ -0,0 +1,26 @@
+name: BVT
+on: [pull_request]
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Build
+        run: make debug
+
+  fmt:
+    name: Format Check
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - run: rustup component add rustfmt
+      - run: make fmt
+  test:
+    name: Run Unit Test
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - run: make test
+