Refactor|FS1: Restructured various file system logics
Moved the logic of Game::isRequiredResource() into FS1::unloadFile() and extracted the logic from FS1::zipLumpIndex() moving it into the tryOpenLump() method.
The subsequently redundant FS1::zipLumpIndex() was removed.
Refactor|FS1: Restructured various file system logics
Moved the logic of Game::isRequiredResource() into FS1::unloadFile()
and extracted the logic from FS1::zipLumpIndex() moving it into the
tryOpenLump() method.
The subsequently redundant FS1::zipLumpIndex() was removed.