machine fixes

The lazy loading causes the following problem:
Let's start with the following set-up:
*all+*style (Pointer) -> myskin (Skin) -> mycss (CSS)
When I change mycss *all+*style+*machine_input gets deleted ( machine.rb:126 )
When I request *all+*style+*machine_output the *all+*style+*machine_input is recreated with
content "[[myskin]]\n[[mycss]]" ( machine_output.rb:5) but a search 
link_to: "mycss" doesn't find  *all+*style+*machine_input ( used in machine_input.rb:22 to get all "dirty" machines). So after another change of mycss the machine output won't be updated. 

this solves the problem for now