This simply adds an extra blank line between the original lxc config
and the template generated options.

In typical use cases, this means that we'll now get the header, then
a blank line, then default.conf content, then a blank line and finally
the template generated config.

The wording of the header is also changed slightly so that it fits in
the usual 80 columns.
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>