ACF1: Fix princess/elder flying very weirdly when punching to direction they look at
ACF1: Force player to press jump to confirm difficulty dialog
To prevent the player from accidentally making a choice too early
don't use colorkey for land spray
this fixes
issue #220
rename ifTransparent to ifColorKey
This should make the name less confusing.
However this image-flag will possibly be dropped completely.
currently irrelevant sdl call adjustment
as suggested by https://wiki.libsdl.org/MigrationGuide