Preperations for block containment checking conversion

[Atdit]

These changes do not change any game mechanics at all, but will be necessary for the upcoming block containment checking conversion from block positions to coordinates. It will make the final conversion PR a lot more smaller and readable. For the conversion to take effect after this PR, the only changes left have to be done in the individual Region.contains(Block block) methods.

Tested.

Important note: I made changes to the cylinder/(hemi)sphere classes getBlocks() methods to remove redundant code, however, I'm unsure if there was an actual intention behind that code. The only usage for getBlocks() is found in portals, which I tested and still worked.