The goal is to replace use of CuboidClipboard with these new classes.
Support for entities, //flip, //rotate, and //distr still needs to be
re-implemented.
DataException was also removed from BaseBlock because The Base(...)
classes should be "dumb" blocks without any validation.
This breaks backwards compatibility for all getWorld() methods, but
shim methods were added for binary compatibility with method calls that
use LocalWorld.
