distro-files: small rework

add files to /etc/skel and /home/astral, move DOOM1.WAD and id1 to /usr/share/games folders and create symlinks to them in the recipe

distro-files/etc/skel/hello.cpp

@@ -0,0 +1,6 @@
+#include <iostream>
+
+int main(){
+	std::cout << "Hello, world!" << std::endl;
+	return 0;
+}