touch responsive animation

This feature adds the ability to get radial feedback when clicking or tapping views. This is done by appending a SVG and animating a growing circle that fades out at the point of the click or tap.

For a view to get this ability it needs to mixin `CocktailsApp.EventFeedback` and call `_radialFeedback` when the event occurs passing the event as its first parameter and an optional callback function.

Note: this feature also fixes some issues with worn params for the tap events in the application.