Alpha 16

Handle missing item images

Made StiLoader use VFSAccessor instead of byte streams
Added toString to StiLoader
Added JavaFx image cache to StiLoader
Added error messages for missing item images
Added two more test examples to intro tab
Refactored and reformatted a few files

Alpha 15

Added more item info on item mapping screen

Alpha 14

Add support for removing item mappings

To remove an item mapping, select it in the mapping list on the right and press the delete key