Fix arch cross-build when running distro cross-build.

Corner case existed when building a cross-arch container (i686 on x86_64)
on a cross-distro host (Fedora container on Ubuntu host).  Fixed the
arch "fixup" code to do the right thing when running from the bootstrap.

Signed-off-by: Michael H. Warfield <mhw@WittsEnd.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Set timezone for new container if not previously defined.

If the container does not already contain an /etc/localtime
timezone definition, then copy a definition from the host to
the container.  This is often a symlink to an appropriate
system timezone definition files and is presumed to exist in

Signed-off-by: Michael H. Warfield <mhw@WittsEnd.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Support SIGPWR in Fedora and Centos containers.

Added code to catch SIGPWR for Upstart in Fedora and CentOS
containers as well as for Systemd in Fedora containers.

Signed-off-by: Michael H. Warfield <mhw@WittsEnd.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Added root_password_expired password control tuning knob.

Added the environment variable "root_password_expired" to
control if the initial, temporary, root password is initially
set up as "expired".  If set to "yes" (default), the root password
is set as "expired" and the user must change it at first login.

Signed-off-by: Michael H. Warfield <mhw@WittsEnd.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>