This class specifies extensions for the CRL in whole.
Use this class to specify extensions for the CRL itself.
The following paragraph is taken from RFC 2459 (Housley, et. al.), part 5.2:
«Each extension in a CRL may be designated as critical or non- critical. A CRL validation MUST fail if it encounters a critical extension which it does not know how to process. However, an unrecognized non-critical extension may be ignored. »
Communities are also allowed to define private CRL extensions to carry information unique to those communities.
All CRLs must contain two following extensions