UI planning
Added more input options for UiObject.
Added ui.Frame
Updated to version 1.6.1 of Pixi.

Large speed boost when using the fire element.
Removed logging the renderer as 1.6.1 Pixi will do that for you.
Fixed NineSlice problem caused by Pixi v1.6.1.

Pixi v1.6.1 appears to set the width/height of the parent
based on the children's positions, which is not wanted for the
NineSlice implementation.