Add github workflows

.github/workflows/build.yml

@@ -0,0 +1,18 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - name: set up JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+      - name: Build with Gradle
+        run: ./gradlew check --stacktrace

.github/workflows/pull-request.yml

@@ -0,0 +1,17 @@
+name: Pull request checks
+
+on: pull_request
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+      - name: set up JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+      - name: Build with Gradle
+        run: ./gradlew check --stacktrace