Restoring ToggleText. We'll create a new ToggleSwitch kind for the visual toggle.

We may get rid of ToggleText since it's no longer used in ToggleItem, but leaving it for now.

Enyo-DCO-1.1-Signed-Off-By: Gray Norton (gray.norton@lge.com)
Adding visual ToggleSwitch control, using it in ToggleItem.

ToggleSwitch replaces ToggleText in ToggleItem, per the latest design.

Besides being more visually obvious, the new design addresses GF-60661 (an issue with localization, since the translations for "on" and "off" are very long in some languages).

Also did some refactoring and cleanup of the LESS / CSS source.

Enyo-DCO-1.1-Signed-Off-By: Gray Norton (gray.norton@lge.com)