Test only on node 0.10

We are not testing a node library. We just need to install some tools from npm.

0.11 errors with some dependency version incompatibility.
Add needed tools to package.json devDependencies

grunt, grunt-cli and bower are not installed on Travis by default.
Install bower dependencies in Travis CI

By default Travis CI would perform `npm install` for node environments.

We need `bower install` as well for `jQuery` and `QUnit` dependencies.

We don't need to track them in the repo, are we?