Run tests via actions

Support running tests via github actions

.github/workflows/elixir.yml

@@ -0,0 +1,26 @@
+name: Elixir CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        otp: ['21.0', '22.0']
+        elixir: ['1.7.2', '1.10.1']
+    steps:
+    - uses: actions/checkout@v2
+    - name: Setup elixir
+      uses: actions/setup-elixir@v1
+      with:
+        elixir-version: ${{matrix.elixir}} # Define the elixir version [required]
+        otp-version: ${{matrix.otp}} # Define the OTP version [required]
+    - name: Install Dependencies
+      run: mix deps.get
+    - name: Run Tests
+      run: mix test