add CI actions

actual tests will still have to be added.

.github/workflows/test.yml

@@ -0,0 +1,33 @@
+name: Tests
+
+on:
+  push:
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/clippy-check@v1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          args: --all-features
+  formatting:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Formatting
+        uses: actions-rs/cargo@v1
+        with:
+          command: fmt
+          args: -- --check
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test