Tiled 0.4.0

• Added support for isometric maps
• Added automatic reloading of tileset images when they change
• Added Offset Map action that can shift a set of layers by a certain amount
• Added a fill tool
• Added ability to duplicate map objects
• Added support for choosing the tile layer data format used when saving
• Added mouse wheel zooming support to the tileset view
• Added an object display color attribute to object groups
• Added ability to edit tile properties through a context menu
• Made writing out a DTD reference optional and disabled it by default
• Made translations functional
• Updated Dutch, Portuguese, Spanish and German translations