Add revoek reason as option with -R

[webservicebe]

When revoking a certificate it always sends 0 (No reason provided or unspecified) as Reason, however in many cases the reason for us is 5 (cessationOfOperation).

It would be nice if we had an option for this also (maybe an extra switch like -R --revoke-reson) The other options 1 (keyCompromise) and 4 (superseded) could also be included