Install busctl and translations

(cherry picked from commit 3853bf74f3102905b6587755781d1a42ea09f9da)
explicitly disable microhttpd

(cherry picked from commit 515ed789804047074e103d0cfb30d478bab5cbe0)
Install the new combined libsystemd0 library
Add new symbols file for libsystemd0.
Update symbols file for libgudev-1.0-0.
Remove pre-generated rules and unit files in debian/rules clean target.

These are generated with rootprefix=/usr and so has the wrong paths for Debian.
Add /run/shm -> /dev/shm symlink in debian/tmpfiles.d/debian.conf
Update /run/initctl symlink target in debian/tmpfiles.d/debian.conf.

/dev/initctl is now a symlink to /run/systemd/initctl/fifo, so make /run/initct point directly to that.
Add users systemd-network, systemd-resolve and systemd-timesync
Remove obsolete build dependencies and configure flags for xattr and tcpwrap.
Disable timesyncd, networkd, resolved and apparmor for udeb
Use debian ntp pool for timesyncd