data using a thread-safe collection. Some NPEs fixed.
More data protection in tiled integration functions (better state
checking, backup tiled-made file before saving ATCS-made data).
jardesc file added for convenience.
CopyOnWriteArrayList, to allow listeners to unregister themselves due to
an event while preventing ConcurrentModificationExceptions.
Modified all GameDataElement.elementChanged concrete implementation to
remove the backlink from the oldOne.An element pointed by an altered
element will not show the game source element in its backlink list
anymore.
handle adding spritesheets. Fixed colorfilters not showing on the
worldmap and replacements simulator. Added "display type" (a.k.a rarity)
item field in the Items comparator.
Added support for the new "colorfilter" map property. Due to Java2D
having no correct color filter support, only the "blackXX" values can be
previwed. "bw" and "invert" cannot, the performance cost was simply way
too high.
Added cool tooltip on the Map replacement simulator showing tiles used
for Ground, Objects and Above layers, as well as coordinates, taking the
active replacements into account.
