Add GitHub Actions CI workflow

.github/workflows/main.yml

@@ -0,0 +1,66 @@
+name: CI
+
+on: [push]
+
+jobs:
+
+  test:
+    name: Test on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macOS-latest]
+
+    steps:
+      - uses: actions/checkout@v1
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+      - name: cargo fetch
+        uses: actions-rs/cargo@v1
+        with:
+          command: fetch
+      - name: Run tests
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --verbose --all
+      - name: Build
+        uses: actions-rs/cargo@v1
+        with:
+          command: build
+          args: --verbose --release
+
+
+  coverage:
+    name: Code Coverage
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+      - name: Run cargo-tarpaulin
+        uses: actions-rs/tarpaulin@v0.1
+        with:
+          version: '0.12.3'
+          timeout: 300
+      - name: Upload coverage report to Codecov
+        uses: codecov/codecov-action@v1
+
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+      - name: Run clippy
+        uses: actions-rs/clippy-check@v1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          args: --all-features