Make backwards-compatible make {xen,unix}-{build,install} targets

This allows us to release the new version of the code and update the
package structure separately.

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

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #14 from djs55/legacy-build-compat

Add the old Makefile targets back in