Comment 9 for bug 1506652

To summarise:
    There are 3 branches, one for wily, vivid, and trusty each.
    juju-core's source has no dep changes, or new files. no copyrights or licences changed.
    The wily debian/tests dir was updated to remove the switch to upstart.
    The wily debian/tests dir was updated to skip future-* tests when the release doesn't support systemd (trusty).
    The wily .pc dir was removed.
    The vivid branch is just a backport of the wily branch
    The trusty branch is just a backport of the wily branch