Revert "Merge branch 'dbus-switch-to-configuration'"

This seems to have combined badly with the systemd upgrade, we'll revert
for now and revisit after the 14.04 branch.

This reverts commit ad80532881119b642d63c7d126e46f4e26cdb0be, reversing
changes made to 1c5d3c78831b5d1aee3b46c2e5cabe7af14bc1d1.