Asynchronous menu loading

[diab0l]

Special menus (like folders) load in a blocking fashion.
That means they are a) not abortable and b) if they point to a virtual share which might not be available and susceptible to timeout or c) a large folder they take fucking forever to either show 'invalid path' or enumerate their contents.

That has annoyed me forever and totally kills responsiveness when i have to steer my mouse around that 'dead network share' or alike.