Added a truly amazing secret area which required rewriting core parts of the engine! The community can have fun searching for and exploring this area.
Now certain "infertile" chunks are not created at all. This is an example of "pruning the chunk tree". For example, consider the block type XAR_YING_FOREST_AIR. This consists of a single gray block in the middle, with sometimes a grower, a shrinker, or a goblin. Now this block type has been set to "prune when infertile" (PWI). When a XAR_YING_FOREST_AIR chunk exists and is fertile, it looks normal. However, as soon as the chunk becomes infertile, the chunk is removed. If we had not set it to be PWI, then when it is infertile it would just have its single block in the middle but no growers, shrinkers, or goblins.
The Xar "block overrides" system has been improved. Now when you override a xar block with a Lua block, the texture of the Lua block will replace the texture of the Xar block. Also, the "is solid" parameters of the Lua block will replace those of the xar block. To make sure that this new system is not tedious, there is a way to copy the basic parameters of a xar block into a Lua block. What you do in the Lua block script is define a function __get_bt_to_copy and have it return something like "XAR_SMALL_YELLOW_FLOWER". Then, you do not need to define the __get_is_solid and __get_tex function of the Lua block (but you can if you want). If you have the __get_bt_to_copy function, it is required to return a string that starts with "XAR_".
