Fixes ENYO-247

## Issue
Tooltips for disabled controls are not hidden when 5-way to a spottable control. The current code handles `onleave` and `onSpotlightBlur` but neither are fired as the cursor hasn't moved and the activating control did not have spotlight focus because it is disabled.

## Fix
Add a listener for the global onSpotlightCurrentChanged. This is fired before onSpotlightFocus so the tooltip will still be appropriately displayed when an enabled activator is spotted. 

Enyo-DCO-1.1-Signed-off-by: Ryan Duffy <ryan.duffy@lge.com>