add grunt jshint to travis

.travis.yml

-language: python
+language:
+  - python
 
 python: 2.7.9
 
@@ -10,8 +11,19 @@ branches:
 
 cache: pip
 
+before_install:
+  - npm install -g grunt-cli
+  - npm install -g bower
+  - cd .build && npm install && bower install && cd ..
+
 script:
   - ./tests/all_tests.py
+  - cd .build && grunt travis && cd ..
+
+cache:
+  directories:
+    - .build/bower_components
+    - .build/node_modules
 
 after_failure:
   - cat ./Logs/sickrage.log