Fix 2014/endoh1/Makefile

I forgot to update the DATA variable when I renamed read_me.md to
spoilers.md.

2014/endoh1/Makefile

@@ -110,7 +110,7 @@ PROG= prog
 #
 OBJ= ${PROG}.o
 DATA= Rakefile alpha.rb assemble.rb ast-def.rb gen-prog.rb gen-table.rb link.rb \
-	machine.rb main.c parse.rb prog-tmpl.c read_me.md register.rb \
+	machine.rb main.c parse.rb prog-tmpl.c spoilers.md register.rb \
 	serialize.rb src.rb tool.rb vm.c
 TARGET= ${PROG} main treacle
 #