Add example service

Signed-off-by: David Scott <dave.scott@citrix.com>
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@citrix.com>
Add Xcp_service.configure2, which uses cmdliner

Using the new interface is not backwards-compatible because
 * we must use "--name-of-arg" rather than "-name-of-arg", hence
   the callers (init scripts) of each package needs to be changed.
 * cmdliner requires more information about the caller, in particular
   'name', 'version' and 'doc'

The old interface still exists and should work as before. Clients can
be upgraded to the new interface one at a time.

Signed-off-by: David Scott <dave.scott@citrix.com>
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@citrix.com>
cmdliner: avoid repeating the 'doc' string

This makes the manpage look nicer.

Signed-off-by: David Scott <dave.scott@citrix.com>
Use cmdliner's converters to give better errors when parsing arguments

Also 'configure2' now returns a result type; the client can choose how
to signal the failure (stderr printing, exit code etc)

Signed-off-by: David Scott <dave.scott@citrix.com>
Improve the output when a 'resource' is missing.

Signed-off-by: David Scott <dave.scott@citrix.com>
Improve the example a bit

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #32 from djs55/add-cmdliner

Add a cmdliner configuration interface