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 test fails when you replace in machine.rb line 127 with 126. It passes again when you uncomment the get request in line 58 in the test. Notice the weird contradiction in line 64/65. 64 always passes, 65 fails.