Fix some typos

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
download: Initial template

This adds a new template called "download". It's a fairly simple
template with a minimal set of dependency which will grab any pre-built
image available on https://images.linuxcontainers.org
Note that the serverside is still work in progress (missing SSL support).

Access is done over https by default with a warning being emitted if
fallback to http was required (may be needed for testing, when behind
proxy and with private servers). All index files and tarballs are
gpg-signed with the default pubkeyid contained in the template itself.

The main benefit of this template is to be entirely
distribution-agnostic, any template that can be integrated with the
server build infrastructure will then work on any LXC machine when using
the download template. This template is also compatible with user
namespaces and will hopefully help widden the number of distros that may
work in unprivileged LXC.

This commit also bundles a small change to the template configs to have
the ubuntu template (used by the download template) to work with
unprivileged LXC.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
cgroup: recursively delete cgroups when asked

Currently when a container is shut down, lxc walks the set of all
cgroup paths it created, in reverse order, and tries to remove them.
This doesn't suffice if the container has also created new cgroups.

It'd be impolite to recursively remove all the cgroup paths we created,
since this can include '/lxc' and thereunder all other containers
started since.

This patch changes container shutdown to only delete the container's own
path, but do so recursively.  Note that if we fail during startup,
the container won't have created any cgroup paths so it the old
way works fine.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
ensure all config items are duplicated on clone/write_config

Since previously I had found a config item that wasn't being propagated
by lxc-clone, I went through all the config items and made sure that:
 a) Each item is documented in lxc.conf
 b) Each item is written out by write_config

The only one that isn't is lxc.include, which by its nature only pulls
in other config item types.

Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>