List, GroupedList: added rendererAdd and rendererRemove events to track when renderers exist for items.
BaseDefaultItemRenderer: fix for null label (closes #282)
TabBar: first and last tab use customTabName in fallbacks, if set (closes #277)
BaseDefaultItemRenderer: accessory positioning (closes #187), Button: label offset, fixes for icon positioning.
PopUpManager: modal overlay resizes when stage resizes (closes #285)
HierarchicalCollection: fix for removing items (closes #283)
BaseDefaultItemRenderer: docs tweaks. accessoryGap defaults to NaN.
Sprite, Image: scrollRect now uses scissorRectangle on RenderSupport (closes #280)
helper vectors for touches (closes #250)
TextFieldTextRenderer: reverted 8422a49e2a6c2d603db08bb2bd292a6e5fe043cf where it waits two frames.
Scale3Image, Scale9Image: access of frame from texture happens only once.
updated build script to create release zip (closes #287)
ListCollection, HierarchicalCollection: made non-final
Sprite: fixes for render support scroll rect (references #280)
removed feathers.display.Image. added feathers.controls.ImageLoader.
ImageLoader: some properties to pass to the internal image, added event metadata, visibility fix.
Updated item renderers to use ImageLoader instead of Image, which allows support for images loaded from URLs (closes #139)
ScrollBar, Slider, ToggleSwitch: removed scrollRect track layout mode
fixed broken docs
build: added missing assets for examples and themes