Rename two methods in HandlerItemStorageFluid

isPreformatted() -> isFormatted() which also got an early exit
preformattedOrContainsFluid() -> allowedByFormat()
(note that the former method name was 75% wrong before)
Fix misspelled fields and methods in code

Methods in ExtraCellsApi were instead deprecated and a properly-spelled
replacement added.
Fix code typos