Better support multiple selections
- Export all selected items into one PEM file
- Batch Revoke/unrevoke/renew of many selected certificates
of the same issuer
- allow exporting templates as PEM
Add Feat. Reg. #83 Option to revoke old certificate when renewing
Always put all signed certificate to the newest CA.
If a CA certificate is renewed, all certificates issued by
the old CA are now shown as signed by the new one.