chore: clarify message for when docs are not generated (#457)

.travis.yml

@@ -31,8 +31,8 @@ os:
 script:
   - npm test
   # make sure when the docs are generated nothing changes (a.k.a. the docs have already been generated)
-  - node scripts/generate-docs.js
-  - git diff --quiet # make sure no files have changed
+  - npm run gendocs
+  - npm run after-travis "Make sure to generate docs!"
 
 # Gitter
 notifications:

package.json

@@ -28,6 +28,7 @@
     "test": "node scripts/run-tests",
     "gendocs": "node scripts/generate-docs",
     "lint": "jshint .",
+    "after-travis": "travis-check-changes",
     "changelog": "bash scripts/changelog.sh"
   },
   "bin": {
@@ -40,7 +41,8 @@
   },
   "devDependencies": {
     "coffee-script": "^1.10.0",
-    "jshint": "^2.9.2"
+    "jshint": "^2.9.2",
+    "travis-check-changes": "^0.2.0"
   },
   "optionalDependencies": {},
   "engines": {