Q doesn't correctly handle floppy disk images with spaces in their path name

[kju]

Steps to reproduce:

1. Edit any virtual machine.
2. In the Hardware tab, go to Floppy -> Choose Imagefile...
3. Choose a floppy image located in a folder with spaces somewhere in its pathname (create with Tools -> Create new Diskimage... if necessary).
4. Boot the system.

Results:

Qemu unexpectedly quit

Error: invalid option -- '-'

and the system fails to start. Advanced -> QEMU Arguments is filled in with the pathname of the floppy after the spaces.

I'd guess this is happening because spaces aren't being quoted when Q calls qemu. I haven't looked at the source code, but maybe Q should shell out to qemu by passing arguments in an array? (Haven't checked if Q does that, but it seems that that may solve this problem).