Update peek.coffee

In the toggleBar function, since this is a jQuery.Event object we can use the event.which property to get the normalized keyCode|charCode property allowing greater cross-browser support.
Merge pull request #38 from leongersing/patch-1

Update peek.coffee for greater browser compatibility
bump to 0.1.6
Include assets from configured view extensions

Using the partial_path of the Peek::View attempt to load the javascript
and stylesheet assets dynamically.

For Peek Item developers: you can use the peek-<extension>.js as a
manifest file to load other dependant assets.
Add peek assets to main app precompile list

This allows us to only download the compiled assets if needed.