Filename relative to the nit-compile folder

Property definitions

nitc $ ExternFile :: filename
	# Filename relative to the nit-compile folder
	var filename: String
src/c_tools.nit:109,2--110,21

nitc $ ExtraJavaFile :: filename
	redef fun filename do return full_name.replace(".", "/") + ".java"
src/ffi/extra_java_files.nit:121,2--67