Create a version task

Add a new grunt task to create a new release version. It can be run like this:
```shell
grunt dist version:patch
````
Running dist before the version task is required so the build artifacts are available. The task uses `npm version` to bump the package version, copies the new version into the bower file and then force commits the dist directory in one shot. If that's successful, the dist directory is deleted in another commit so that no one accidentally makes patches against those files.

With the bower.json file now directly in the repo, I think it should be possible to retire [video.js-component](https://github.com/videojs/video.js-component)