Support of all features of RFC 2560 and RFC 6960:
 - HTTP Get of small request
 - Evaluate request extension PreferredSignatureAlgorithms
 - Support response extension ArchiveCutoff
 - Support response extension CrlID
 - Support of response extension ExtendedRevoke introduced in RFC 6960
 - Add option to configure whether to inherit CA revocation
 - More precise control of certificates included in response
 - The format of the configuration file of OCSP responder has been changed.
add new features:
  - unrevoke certificate
  - remove certificate
  - revoke CA
  - unrevoke CA