Tweak container initialization to make upstart/init happier

Tweak container initialization to make upstart/init happier

Upstart crashes & burns in a heap if $TERM environment variable
is missing. Presumably the kernel always sets this when booting
init on a real machine, so libvirt should set it for containers
too.

To make a typical inittab / mingetty setup happier, we need to
symlink the primary console /dev/pts/0 to /dev/tty1.

Improve logging in certain scenarios to make troubleshooting
easier

* src/lxc/lxc_container.c: Create /dev/tty1 and set $TERM