Fix the path of the videojs ads plugin

Tests are failing because of a bad path in the Gruntfile; The jasmine
configuration has an incorrect path for the ads plugin. Fix by adding
missing 'js'
Update videojs-contrib-ads to 0.4.0
Pull in the latest version of videojs-contrib-ads. Trigger an ads request during plugin initiatlization if there is already content in the player. Add grunt-connect as a dev dependency to make it a tiny bit easier to load up the example page over HTTP.
Merge pull request #37 from jcruz2us/fix-path-to-ads-plugin

Fix the path of the videojs ads plugin
Merge branch 'dmlap-contrib-ads-0.4'
Merge