update Debian Jessie systemd to backports without breakage

update Debian Jessie systemd to backports without breakage

# Although I never use aptitude, I found it very useful today to update
# systemd to backports without system breakage. I define system breakage
# as attempting to upgrade a package which then removes a bunch of
# important packages.
#
# These were the commands I ran to get the final command. I will have to
# create a fresh Jessie install and rerun them to provide an explanation
# for each change:
#
# $ which aptitude
#     This returned no results, aptitude was not installed
# $ sudo apt-get -s install aptitude
#     Checked to see what it was going to install along with aptitude
# $ sudo apt-get install aptitude
#     Looks good, install
# $ man aptitude
#     I don't use aptitude, so time to read the manual
# $ sudo aptitude -s install systemd/jessie-backports
#     Check to see what aptitude says <now have to run again in fresh
#     jessie install to see again what triggered the next modifications>
# $ sudo aptitude -s install systemd/jessie-backports libpam-systemd/jessie-backports systemd-sysv/jessie-backports
# $ sudo aptitude -s install systemd/jessie-backports libpam-systemd/jessie-backports systemd-sysv/jessie-backports libapparmor1/jessie-backports libsystemd0/jessie-backports
# $ sudo aptitude -s install systemd/jessie-backports libpam-systemd/jessie-backports systemd-sysv/jessie-backports libapparmor1/jessie-backports libsystemd0/jessie-backports ifupdown/jessie-backports udev/jessie-backports
# $ sudo aptitude -s install systemd/jessie-backports libpam-systemd/jessie-backports systemd-sysv/jessie-backports libapparmor1/jessie-backports libsystemd0/jessie-backports ifupdown/jessie-backports udev/jessie-backports libudev1/jessie-backports

$ sudo apt-get install systemd/jessie-backports \
                       libpam-systemd/jessie-backports \
                       systemd-sysv/jessie-backports \
                       libapparmor1/jessie-backports \
                       libsystemd0/jessie-backports \
                       ifupdown/jessie-backports \
                       udev/jessie-backports \
                       libudev1/jessie-backports \
                       systemd-container/jessie-backports \
                       systemd-ui