archive: preserve hardlinks in Tar and Untar

* integration test for preserving hardlinks

Signed-off-by: Vincent Batts <vbatts@redhat.com>
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
archive: example app for diffing directories

By default is a demo of file differences, but can be used to create a
tar of changes between an old and new path.

Signed-off-by: Vincent Batts <vbatts@redhat.com>
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
archive: cleanup and more information

Signed-off-by: Vincent Batts <vbatts@redhat.com>
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>