Badges issuername and contact per backpack.

Remove config settings badges_defaultissuername and badges_defaultissuercontact

We should have an issuername and issuercontact for each backpack.

This will be important when we can have multiple active backpacks.

This is tricky because the default should come from the other config settings SITENAME and support email - which may have not been set when the badge creates the default backpacks.