(This is not expected to be their final location, but it makes them easier to relocate when necessary, and easier for users to edit until the whole project's file structure is finalized.)
WATRTILE was wrongly defined as 15, and WALLTILE as 1. Those had to be
flipped around.
This has allowed for us to replace inmediate values with these constants
in several places to improve readability.
WATRTILE was renamed to WATERTILE in the name of readability.