* Merge from debian unstable. Remaining changes:
  - debian/patches/9004_ubuntu_fix_tree_support.patch: Fix tree detection
    for all ISO/HTTP source, to not longer fail with cobbler/koan.
  - debian/patches/9005_ubuntu_releases.patch: Add recent releases, and
    update EoL releases.
  - debian/{control,rules,pyversions}: Build using dh_python2, use
    debhelper v8 instead of cdbs; for some reason the package build an
    empty binary package when using dh_python2.
  - debian/control: added acl package to depends.
  - debian/control: added libvirt-bin to recommends
* Dropped changes:
  - debian/patches/9003-fix-path-to-hvmloader-in-testsuite.patch,
    debian/patches/0004-Fix-path-to-qemu-dm.patch: xen binaries haven't
    been in /usr/lib/xen-default for a while, so either these patches
    were broken, or unnecessary.