feat #994 MultiAutoComplete: Highlighted mode interactions

This pull request allows users to do the following:
1) When the user left-clicks on an item (that is not already highlighted),
it becomes highlighted (if any other was already highlighted, it becomes
de-highlighted)
2) When the user left-clicks on an already highlighted item, the latter
goes into edit-mode.
3) When an item is highlighted, pressing the backspace key removes the
item and the previous one becomes highlighted. If there is no previous
one, the following one becomes highlighted
4) When an item is highlighted, pressing the delete key removes the item
and the following one becomes highlighted

Close #994.
Expanded Button feature for MultiAutoComplete
fix #1014 Adding MultiAutoComplete highlight properties in AriaSkinBeans

In commit d31b18d16fb9d20413ebb1e8d702e68c82dd6582 (corresponding to #985),
some properties were added to the skin, but were not added to AriaSkinBeans.
This commit adds these properties to AriaSkinBeans.
feat #941 Added color animations and show/hide features, relative sizes and anim control (skip/pause/resume)

- implemented color animations (color name, hexadecimal or RGB notation are accepted)
- show, hide and toggle methods display or hide elements by animating "height", "width" or "opacity" properties
- values like "+=50px" or "-=5%" are accepted
- skip, pause and resume methods for both animations and queues are provided.
- deleted color list except for the 17 fundamental ones
- some minor code improvements
Close #941