Support 'npm run ci' for Continuous Integration

This will be run in the Azure Pipeline that tests GitGitGadget itself.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

.gitignore

@@ -4,4 +4,4 @@
 /build/
 /node_modules/
 /npm-debug.log
-
+/junit.xml

package.json

@@ -13,7 +13,8 @@
     "lint": "tslint -c tslint.json '{lib,script,tests}/**/*.{ts,tsx}'",
     "start": "node server.js",
     "test": "tslint --project . && jest --env=node",
-    "test:watch": "jest --watch --notify --notifyMode=change --coverage"
+    "test:watch": "jest --watch --notify --notifyMode=change --coverage",
+    "ci": "tslint --project . && jest --env=node --ci --reporters=default --reporters=jest-junit"
   },
   "bugs": {
     "url": "https://github.com/gitgitgadget/gitgitgadget/issues"