Add a new secret type known as "passphrase" - it will handle adding the
secret objects that need a passphrase without a specific username.
The format is:
<secret ...>
<uuid>...</uuid>
...
<usage type='passphrase'>
<name>mumblyfratz</name>
</usage>
</secret>
Signed-off-by: John Ferlan <jferlan@redhat.com>
