[cloud] #68: support HVM instances in EC2

[Fedora Cloud Trac Tickets]

#68: support HVM instances in EC2
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 Reporter:  mattdm            |      Owner:
     Type:  task              |     Status:  new
 Priority:  normal            |  Milestone:  Fedora 21 (Alpha)
Component:  Cloud Base Image  |   Keywords:
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 We currently only support Xen paravirtualized images (PV) in EC2. We need
 to support HVM as well.

(This will require changes to our EC2 image production and upload process,
 and may require changes to our bootloader code as well. Particularly, it
 probably takes away our clever hack for providing different kernel
 parameters in EC2.)