refs #33 - Added IE6 support

* Added IE6 support using already existing code
* Added a function for each VM to do specific setup
* Added a function to download drivers in a specific directory for each VM
* Added a function to build and attach an ISO containing drivers for the VM
Rearrange XP driver so clean snapshot has mounted image
Update README for IE6 support and fix indentation
Merge branch 'jubianchi-ie6'
Assume Yes on all queries
Merge remote-tracking branch 'rcmachado/master'
Tweak curl stuff further and add resume to all downloads where supported. Update readme
Merge remote-tracking branch 'jaytaph/master'
Add cabextract for IE6 since MS just changed formats
Merge branch 'cabextract'
Better checks for ext pack versions fixes #9 #27 #46 #57 #68 #71 #74 #77 #83 #89 #95 #96 and half of #94
Download GA ISO if not found.
Typo.
Only download GA ISO if it doesn't exist.
Add version number to GA ISO locally.
Check version earlier for GA ISO.