Update to new metadata format

Signed-off-by: David Scott <dave.scott@citrix.com>
.travis: remove use of TRAVIS_OS_NAME

This is not a multi-OS repo.

Signed-off-by: David Scott <dave.scott@citrix.com>
vhdlib: add depexts for blktap-dev

Signed-off-by: David Scott <dave.scott@citrix.com>
vhdlib: also depends on uuid-dev

Signed-off-by: David Scott <dave.scott@citrix.com>
Attempt to upgrade libvirt via ubuntu-virt ppa

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #23 from djs55/metadata-upgrade

Update to new metadata format