tasks: print eslint version before linting

Author: etpinard

package.json

@@ -28,7 +28,7 @@
     "build": "npm run preprocess && npm run bundle && npm run header && npm run stats",
     "cibuild": "npm run preprocess && node tasks/cibundle.js",
     "watch": "node tasks/watch.js",
-    "lint": "eslint . || true",
+    "lint": "eslint --version && eslint . || true",
     "lint-fix": "eslint . --fix",
     "pretest": "node tasks/pretest.js",
     "test-jasmine": "karma start test/jasmine/karma.conf.js",