inv-touch works differently to other inventory commands

[PeterJCLaw]

I forget exactly what the error was, but I recall hitting an issue when trying to use inv-touch with assemblies at the check-in event last weekend.
I think there was another command which struggled too, but I can't recall which it was.

[PeterJCLaw]

Hrm, looks like this is more general -- inv-touch expects to be given a relative path to the asset in question, rather than a part code.

Probably the solution here is to change inv-touch so that it works on part codes.