set up CI with Azure Pipelines

[skip ci]

Author: lurock

azure-pipelines.yml

@@ -0,0 +1,17 @@
+
+trigger:
+- master
+
+pool:
+  vmImage: ubuntu-latest
+
+steps:
+- task: NodeTool@0
+  inputs:
+    versionSpec: '10.x'
+  displayName: 'Install Node.js'
+
+- script: |
+    npm install
+    npm test
+  displayName: 'npm test'