Description of problem:
When I try to use liveusb-creator to put a (non-Fedora) iso which has no md5 information onto a USB stick, liveusb-creator says "ISO MD5 checksum verification failed" and refuses to write the iso

Version-Release number of selected component (if applicable):
3.9.3-1

How reproducible:
always

Steps to Reproduce:
1. download an iso without md5 information
2. run liveusb-creator, select the iso, click "create live usb"
  
Actual results:
liveusb-creator fails

Expected results:
liveusb-creator writes iso to usb

Additional info:
It makes total sense that you would want liveusb-creator to refuse to write, if md5 verification fails. But when md5 info is absent, liveusb-creator should run (perhaps with a warning.) At the very least, liveusb-creator should announce, "quit and run again with the -n option to disable md5 verification". 

spoo:~/Downloads$ checkisomd5 ubuntu-10.10-desktop-i386.iso 
Press [Esc] to abort check.

The media check is complete, the result is: NA.

No checksum information available, unable to verify media.
spoo:~/Downloads$