This massive image modification removes colour profile information and adds an alpha channel.
The first saves a little space, the second costs a little space. First is needed since SDL on OSX applies colour profile info which, while cool, is useless so long as the other theme colours are un-adjusted. Second is since we are apparently requiring full 32 bit surfaces now.
install(FILES
icon.png
mouton2.png
Border.png
mouton3.png
mouton4.png
fleurland2.png
grassp.png
grass.png
theme.cfg
fleurland3.png
grass2.png
fleurland4.png
Girder.png
mouton1.png
barriere.png
rocher.png
Flake.png
horizont.png
Sky.png
LandTex.png
grassp2.png
fleurland.png
fleur.png
Clouds.png
horizont-lowres.png
Sky-lowres.png
DESTINATION ${SHAREPATH}Data/Themes/Sheep)