Small refactors
Minor changes that fix some bugs and improvement the UI
Merge pull request #447 from RotaruDan/UI-improvements

UI improvements
Added an undefined progress bar icon.
Added Notification widget.
Minor UI widgets improvements.
Merge pull request #457 from anserran/smallrefactors

Small refactors
Use foreach instead of iterators for Model iteration
 * Model.getIndex() is now Model.listNamedEntities()
 * it is an Iterable instead of an Iterator
 * updated dependencies
Fix index (closes #362)  * now uses Lucene 3.6.2 + lucene-analyzers  * search is full-substring instead of prefix-only  * entire object hierarchy is indexed
Merge pull request #445 from manuel-freire/fix-index-test

Fix index test
Merge pull request #456 from RotaruDan/notifications

Notifications
Added check to OpenGame to ensure EditState has a editScene
Merge pull request #461 from anserran/editopen

Added check to OpenGame to ensure EditState has a editScene
Initialize, release and build timelines added to the tweens widget.
Adapted TweenButton and TweenDragButton in order to get initialized correctly.
Improved tween functionality code readability.
A first approach to a repository implementation.
ElementButton improvements.
Download, unzip and display the repository thumbnails.
Fixed Android skin loading path.