Made stronghold generation thread safe and fixed crashing when opening superflat worlds.

使要塞生成线程安全，并修复了打开超平坦世界时的崩溃。

Fix issue #2 caused by v1.0.4.

修复由v1.0.4导致的问题#2。

Stability improvements and added some log messages.

稳定性改进并添加了一些日志消息。

No longer crashes when loading already existing worlds.

加载现有世界时不再崩溃。

Bug fixes + is now compatible with custom dimensions.

修复bug+现在与自定义维度兼容。

Fixed(hopefully) a bug that very rarely caused chunk errors.

修复了（希望如此）一个导致区块错误的罕见的bug。

Generates strongholds on a seperate thread to speed up the loading screen.

在世界生成时将要塞放在一个单独的线程上生成来加快世界生成速度。