Add gitlab-ci template

.gitignore

@@ -65,4 +65,3 @@ hs_err_pid*
 
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
-

.gitlab-ci.yml

@@ -0,0 +1,18 @@
+# Based on https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Gradle.gitlab-ci.yml
+image: gradle:alpine
+
+variables:
+  GRADLE_OPTS: "-Dorg.gradle.daemon=false"
+
+before_script:
+  - export GRADLE_USER_HOME=`pwd`/.gradle
+
+build:
+  stage: build
+  script: gradle --build-cache assemble
+  cache:
+    key: "$CI_COMMIT_REF_NAME"
+    policy: push
+    paths:
+      - build
+      - .gradle