set up github actions

.github/workflows/rust.yml

@@ -0,0 +1,32 @@
+name: Rust
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Cache
+      uses: actions/cache@v2
+      with:
+        path: |
+          ~/.cargo
+          target/
+        key: ${{ runner.os }}-${{ hashFiles('Cargo.toml') }}
+        restore-keys: |
+          ${{ runner.os }}-${{ hashFiles('Cargo.toml') }}
+          ${{ runner.os }}-
+    - name: Build
+      run: cargo build --verbose
+    - name: Run tests
+      run: cargo test --verbose