ci(gh): adds github actions

re #175

Author: waynevanson

.github/workflows/build.yaml

@@ -0,0 +1,46 @@
+name: Node.js CI
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: [ubuntu-latest]
+
+    strategy:
+      matrix:
+        # Maintenance versions of node
+        node-version: [10.x, 12.x, 14.x]
+
+    steps:
+      - uses: actions/checkout@v2
+
+        # todo - lint commit messages
+
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Get yarn cache directory path
+        id: yarn-cache-dir-path
+        run: echo "::set-output name=dir::$(yarn cache dir)"
+
+      - uses: actions/cache@v2
+        id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
+        with:
+          path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
+          key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-yarn-
+
+      - name: Install dependencies
+        run: yarn --frozen-lockfile
+
+      - run: yarn build --if-present
+        # todo - make tests
+        # - run: yarn test:unit
+        # - run: yarn test:compatability
+
+        # todo - deploy in different action?
+        env:
+          CI: true