* complete scrollbar skin
* implement scrollbar functionality (scrolling with mouse)
* fix onMouseClick issues
* add tabs in options (graphics and general tab)
* add new option for limiting frame rate using scrollbar
* add new widget property "clipping" that will be used on scrollable areas
* implement draw clipping using opengl stencil buffers
* allow to create Widgets by style name with g_ui.createWidgetByStyle
* styles can now have children widgets
* make proper use of the isNotPathable in pathfinding
* add scrollbar skin