Test if the application was bound to a platform, if not crash

Property definitions

app :: app_base $ Sys :: test_bound_platform
# Test if the application was bound to a platform, if not crash
private fun test_bound_platform
do
	print_error "Apps must be bound to a platform at compilation using `-m linux` or `-m android`"
	exit 1
end
lib/app/app_base.nit:125,1--130,3

linux :: linux $ Sys :: test_bound_platform
redef fun test_bound_platform do end
lib/linux/linux.nit:67,1--36

android :: platform $ Sys :: test_bound_platform
redef fun test_bound_platform do end
lib/android/platform.nit:27,1--36