code: public void revoke(User revoker, String revokee, String reason) throws RevocationException, InvalidArgumentException {
          revokeInternal(revoker, revokee, reason, false);
      }
docs: revoke one user (including his all enrollments)
  
  @param revoker admin user who has revoker attribute configured in CA-server
  @param revokee user who is to be revoked
  @param reason  revoke reason, see RFC 5280
  @throws RevocationException
  @throws InvalidArgumentException